836f32e769
The common pattern `iter::repeat(elt).take(n).collect::<Vec<_>>()` is exactly equivalent to `vec![elt; n]`, do this replacement in the whole tree. (Actually, vec![] is smart enough to only call clone n - 1 times, while the former solution would call clone n times, and this fact is virtually irrelevant in practice.)
900 lines
30 KiB
Rust
900 lines
30 KiB
Rust
// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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//! Generate files suitable for use with [Graphviz](http://www.graphviz.org/)
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//!
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//! The `render` function generates output (e.g. an `output.dot` file) for
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//! use with [Graphviz](http://www.graphviz.org/) by walking a labelled
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//! graph. (Graphviz can then automatically lay out the nodes and edges
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//! of the graph, and also optionally render the graph as an image or
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//! other [output formats](
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//! http://www.graphviz.org/content/output-formats), such as SVG.)
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//!
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//! Rather than impose some particular graph data structure on clients,
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//! this library exposes two traits that clients can implement on their
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//! own structs before handing them over to the rendering function.
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//!
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//! Note: This library does not yet provide access to the full
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//! expressiveness of the [DOT language](
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//! http://www.graphviz.org/doc/info/lang.html). For example, there are
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//! many [attributes](http://www.graphviz.org/content/attrs) related to
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//! providing layout hints (e.g. left-to-right versus top-down, which
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//! algorithm to use, etc). The current intention of this library is to
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//! emit a human-readable .dot file with very regular structure suitable
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//! for easy post-processing.
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//!
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//! # Examples
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//!
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//! The first example uses a very simple graph representation: a list of
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//! pairs of ints, representing the edges (the node set is implicit).
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//! Each node label is derived directly from the int representing the node,
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//! while the edge labels are all empty strings.
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//!
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//! This example also illustrates how to use `Cow<[T]>` to return
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//! an owned vector or a borrowed slice as appropriate: we construct the
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//! node vector from scratch, but borrow the edge list (rather than
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//! constructing a copy of all the edges from scratch).
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//!
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//! The output from this example renders five nodes, with the first four
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//! forming a diamond-shaped acyclic graph and then pointing to the fifth
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//! which is cyclic.
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//!
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//! ```rust
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//! # #![feature(rustc_private, core, into_cow)]
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//! use std::borrow::IntoCow;
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//! use std::io::Write;
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//! use graphviz as dot;
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//!
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//! type Nd = isize;
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//! type Ed = (isize,isize);
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//! struct Edges(Vec<Ed>);
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//!
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//! pub fn render_to<W: Write>(output: &mut W) {
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//! let edges = Edges(vec!((0,1), (0,2), (1,3), (2,3), (3,4), (4,4)));
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//! dot::render(&edges, output).unwrap()
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//! }
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//!
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//! impl<'a> dot::Labeller<'a, Nd, Ed> for Edges {
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//! fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new("example1").unwrap() }
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//!
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//! fn node_id(&'a self, n: &Nd) -> dot::Id<'a> {
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//! dot::Id::new(format!("N{}", *n)).unwrap()
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//! }
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//! }
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//!
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//! impl<'a> dot::GraphWalk<'a, Nd, Ed> for Edges {
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//! fn nodes(&self) -> dot::Nodes<'a,Nd> {
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//! // (assumes that |N| \approxeq |E|)
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//! let &Edges(ref v) = self;
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//! let mut nodes = Vec::with_capacity(v.len());
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//! for &(s,t) in v {
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//! nodes.push(s); nodes.push(t);
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//! }
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//! nodes.sort();
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//! nodes.dedup();
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//! nodes.into_cow()
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//! }
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//!
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//! fn edges(&'a self) -> dot::Edges<'a,Ed> {
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//! let &Edges(ref edges) = self;
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//! (&edges[..]).into_cow()
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//! }
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//!
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//! fn source(&self, e: &Ed) -> Nd { let &(s,_) = e; s }
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//!
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//! fn target(&self, e: &Ed) -> Nd { let &(_,t) = e; t }
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//! }
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//!
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//! # pub fn main() { render_to(&mut Vec::new()) }
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//! ```
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//!
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//! ```no_run
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//! # pub fn render_to<W:std::io::Write>(output: &mut W) { unimplemented!() }
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//! pub fn main() {
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//! use std::fs::File;
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//! let mut f = File::create("example1.dot").unwrap();
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//! render_to(&mut f)
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//! }
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//! ```
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//!
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//! Output from first example (in `example1.dot`):
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//!
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//! ```ignore
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//! digraph example1 {
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//! N0[label="N0"];
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//! N1[label="N1"];
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//! N2[label="N2"];
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//! N3[label="N3"];
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//! N4[label="N4"];
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//! N0 -> N1[label=""];
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//! N0 -> N2[label=""];
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//! N1 -> N3[label=""];
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//! N2 -> N3[label=""];
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//! N3 -> N4[label=""];
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//! N4 -> N4[label=""];
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//! }
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//! ```
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//!
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//! The second example illustrates using `node_label` and `edge_label` to
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//! add labels to the nodes and edges in the rendered graph. The graph
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//! here carries both `nodes` (the label text to use for rendering a
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//! particular node), and `edges` (again a list of `(source,target)`
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//! indices).
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//!
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//! This example also illustrates how to use a type (in this case the edge
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//! type) that shares substructure with the graph: the edge type here is a
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//! direct reference to the `(source,target)` pair stored in the graph's
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//! internal vector (rather than passing around a copy of the pair
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//! itself). Note that this implies that `fn edges(&'a self)` must
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//! construct a fresh `Vec<&'a (usize,usize)>` from the `Vec<(usize,usize)>`
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//! edges stored in `self`.
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//!
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//! Since both the set of nodes and the set of edges are always
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//! constructed from scratch via iterators, we use the `collect()` method
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//! from the `Iterator` trait to collect the nodes and edges into freshly
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//! constructed growable `Vec` values (rather use the `into_cow`
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//! from the `IntoCow` trait as was used in the first example
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//! above).
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//!
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//! The output from this example renders four nodes that make up the
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//! Hasse-diagram for the subsets of the set `{x, y}`. Each edge is
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//! labelled with the ⊆ character (specified using the HTML character
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//! entity `&sube`).
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//!
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//! ```rust
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//! # #![feature(rustc_private, core, into_cow)]
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//! use std::borrow::IntoCow;
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//! use std::io::Write;
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//! use graphviz as dot;
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//!
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//! type Nd = usize;
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//! type Ed<'a> = &'a (usize, usize);
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//! struct Graph { nodes: Vec<&'static str>, edges: Vec<(usize,usize)> }
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//!
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//! pub fn render_to<W: Write>(output: &mut W) {
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//! let nodes = vec!("{x,y}","{x}","{y}","{}");
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//! let edges = vec!((0,1), (0,2), (1,3), (2,3));
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//! let graph = Graph { nodes: nodes, edges: edges };
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//!
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//! dot::render(&graph, output).unwrap()
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//! }
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//!
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//! impl<'a> dot::Labeller<'a, Nd, Ed<'a>> for Graph {
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//! fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new("example2").unwrap() }
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//! fn node_id(&'a self, n: &Nd) -> dot::Id<'a> {
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//! dot::Id::new(format!("N{}", n)).unwrap()
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//! }
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//! fn node_label<'b>(&'b self, n: &Nd) -> dot::LabelText<'b> {
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//! dot::LabelText::LabelStr(self.nodes[*n].as_slice().into_cow())
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//! }
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//! fn edge_label<'b>(&'b self, _: &Ed) -> dot::LabelText<'b> {
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//! dot::LabelText::LabelStr("⊆".into_cow())
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//! }
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//! }
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//!
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//! impl<'a> dot::GraphWalk<'a, Nd, Ed<'a>> for Graph {
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//! fn nodes(&self) -> dot::Nodes<'a,Nd> { (0..self.nodes.len()).collect() }
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//! fn edges(&'a self) -> dot::Edges<'a,Ed<'a>> { self.edges.iter().collect() }
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//! fn source(&self, e: &Ed) -> Nd { let & &(s,_) = e; s }
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//! fn target(&self, e: &Ed) -> Nd { let & &(_,t) = e; t }
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//! }
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//!
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//! # pub fn main() { render_to(&mut Vec::new()) }
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//! ```
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//!
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//! ```no_run
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//! # pub fn render_to<W:std::io::Write>(output: &mut W) { unimplemented!() }
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//! pub fn main() {
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//! use std::fs::File;
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//! let mut f = File::create("example2.dot").unwrap();
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//! render_to(&mut f)
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//! }
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//! ```
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//!
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//! The third example is similar to the second, except now each node and
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//! edge now carries a reference to the string label for each node as well
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//! as that node's index. (This is another illustration of how to share
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//! structure with the graph itself, and why one might want to do so.)
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//!
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//! The output from this example is the same as the second example: the
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//! Hasse-diagram for the subsets of the set `{x, y}`.
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//!
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//! ```rust
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//! # #![feature(rustc_private, core, into_cow)]
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//! use std::borrow::IntoCow;
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//! use std::io::Write;
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//! use graphviz as dot;
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//!
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//! type Nd<'a> = (usize, &'a str);
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//! type Ed<'a> = (Nd<'a>, Nd<'a>);
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//! struct Graph { nodes: Vec<&'static str>, edges: Vec<(usize,usize)> }
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//!
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//! pub fn render_to<W: Write>(output: &mut W) {
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//! let nodes = vec!("{x,y}","{x}","{y}","{}");
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//! let edges = vec!((0,1), (0,2), (1,3), (2,3));
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//! let graph = Graph { nodes: nodes, edges: edges };
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//!
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//! dot::render(&graph, output).unwrap()
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//! }
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//!
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//! impl<'a> dot::Labeller<'a, Nd<'a>, Ed<'a>> for Graph {
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//! fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new("example3").unwrap() }
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//! fn node_id(&'a self, n: &Nd<'a>) -> dot::Id<'a> {
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//! dot::Id::new(format!("N{}", n.0)).unwrap()
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//! }
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//! fn node_label<'b>(&'b self, n: &Nd<'b>) -> dot::LabelText<'b> {
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//! let &(i, _) = n;
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//! dot::LabelText::LabelStr(self.nodes[i].into_cow())
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//! }
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//! fn edge_label<'b>(&'b self, _: &Ed<'b>) -> dot::LabelText<'b> {
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//! dot::LabelText::LabelStr("⊆".into_cow())
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//! }
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//! }
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//!
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//! impl<'a> dot::GraphWalk<'a, Nd<'a>, Ed<'a>> for Graph {
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//! fn nodes(&'a self) -> dot::Nodes<'a,Nd<'a>> {
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//! self.nodes.iter().map(|s| &s[..]).enumerate().collect()
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//! }
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//! fn edges(&'a self) -> dot::Edges<'a,Ed<'a>> {
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//! self.edges.iter()
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//! .map(|&(i,j)|((i, &self.nodes[i][..]),
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//! (j, &self.nodes[j][..])))
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//! .collect()
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//! }
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//! fn source(&self, e: &Ed<'a>) -> Nd<'a> { let &(s,_) = e; s }
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//! fn target(&self, e: &Ed<'a>) -> Nd<'a> { let &(_,t) = e; t }
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//! }
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//!
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//! # pub fn main() { render_to(&mut Vec::new()) }
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//! ```
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//!
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//! ```no_run
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//! # pub fn render_to<W:std::io::Write>(output: &mut W) { unimplemented!() }
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//! pub fn main() {
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//! use std::fs::File;
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//! let mut f = File::create("example3.dot").unwrap();
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//! render_to(&mut f)
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//! }
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//! ```
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//!
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//! # References
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//!
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//! * [Graphviz](http://www.graphviz.org/)
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//!
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//! * [DOT language](http://www.graphviz.org/doc/info/lang.html)
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// Do not remove on snapshot creation. Needed for bootstrap. (Issue #22364)
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#![cfg_attr(stage0, feature(custom_attribute))]
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#![crate_name = "graphviz"]
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#![unstable(feature = "rustc_private")]
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#![feature(staged_api)]
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#![staged_api]
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#![crate_type = "rlib"]
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#![crate_type = "dylib"]
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#![doc(html_logo_url = "http://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
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html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
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html_root_url = "http://doc.rust-lang.org/nightly/")]
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#![feature(into_cow)]
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#![feature(str_escape)]
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use self::LabelText::*;
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use std::borrow::{IntoCow, Cow};
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use std::io::prelude::*;
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use std::io;
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/// The text for a graphviz label on a node or edge.
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pub enum LabelText<'a> {
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/// This kind of label preserves the text directly as is.
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///
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/// Occurrences of backslashes (`\`) are escaped, and thus appear
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/// as backslashes in the rendered label.
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LabelStr(Cow<'a, str>),
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/// This kind of label uses the graphviz label escString type:
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/// http://www.graphviz.org/content/attrs#kescString
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///
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/// Occurrences of backslashes (`\`) are not escaped; instead they
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/// are interpreted as initiating an escString escape sequence.
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///
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/// Escape sequences of particular interest: in addition to `\n`
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/// to break a line (centering the line preceding the `\n`), there
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/// are also the escape sequences `\l` which left-justifies the
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/// preceding line and `\r` which right-justifies it.
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EscStr(Cow<'a, str>),
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}
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// There is a tension in the design of the labelling API.
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//
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// For example, I considered making a `Labeller<T>` trait that
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// provides labels for `T`, and then making the graph type `G`
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// implement `Labeller<Node>` and `Labeller<Edge>`. However, this is
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// not possible without functional dependencies. (One could work
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// around that, but I did not explore that avenue heavily.)
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//
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// Another approach that I actually used for a while was to make a
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// `Label<Context>` trait that is implemented by the client-specific
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// Node and Edge types (as well as an implementation on Graph itself
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// for the overall name for the graph). The main disadvantage of this
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// second approach (compared to having the `G` type parameter
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// implement a Labelling service) that I have encountered is that it
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// makes it impossible to use types outside of the current crate
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// directly as Nodes/Edges; you need to wrap them in newtype'd
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// structs. See e.g. the `No` and `Ed` structs in the examples. (In
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// practice clients using a graph in some other crate would need to
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// provide some sort of adapter shim over the graph anyway to
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// interface with this library).
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//
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// Another approach would be to make a single `Labeller<N,E>` trait
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// that provides three methods (graph_label, node_label, edge_label),
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// and then make `G` implement `Labeller<N,E>`. At first this did not
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// appeal to me, since I had thought I would need separate methods on
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// each data variant for dot-internal identifiers versus user-visible
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// labels. However, the identifier/label distinction only arises for
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// nodes; graphs themselves only have identifiers, and edges only have
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// labels.
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//
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// So in the end I decided to use the third approach described above.
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/// `Id` is a Graphviz `ID`.
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pub struct Id<'a> {
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name: Cow<'a, str>,
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}
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impl<'a> Id<'a> {
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/// Creates an `Id` named `name`.
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///
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/// The caller must ensure that the input conforms to an
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/// identifier format: it must be a non-empty string made up of
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/// alphanumeric or underscore characters, not beginning with a
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/// digit (i.e. the regular expression `[a-zA-Z_][a-zA-Z_0-9]*`).
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///
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/// (Note: this format is a strict subset of the `ID` format
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/// defined by the DOT language. This function may change in the
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/// future to accept a broader subset, or the entirety, of DOT's
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/// `ID` format.)
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///
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/// Passing an invalid string (containing spaces, brackets,
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/// quotes, ...) will return an empty `Err` value.
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pub fn new<Name: IntoCow<'a, str>>(name: Name) -> Result<Id<'a>, ()> {
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let name = name.into_cow();
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{
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let mut chars = name.chars();
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match chars.next() {
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Some(c) if is_letter_or_underscore(c) => { ; },
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_ => return Err(())
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}
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if !chars.all(is_constituent) {
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return Err(())
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}
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}
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return Ok(Id{ name: name });
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fn is_letter_or_underscore(c: char) -> bool {
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in_range('a', c, 'z') || in_range('A', c, 'Z') || c == '_'
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}
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fn is_constituent(c: char) -> bool {
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is_letter_or_underscore(c) || in_range('0', c, '9')
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}
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fn in_range(low: char, c: char, high: char) -> bool {
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low as usize <= c as usize && c as usize <= high as usize
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}
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}
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pub fn as_slice(&'a self) -> &'a str {
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&*self.name
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}
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pub fn name(self) -> Cow<'a, str> {
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self.name
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}
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}
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/// Each instance of a type that implements `Label<C>` maps to a
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/// unique identifier with respect to `C`, which is used to identify
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/// it in the generated .dot file. They can also provide more
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/// elaborate (and non-unique) label text that is used in the graphviz
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/// rendered output.
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/// The graph instance is responsible for providing the DOT compatible
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/// identifiers for the nodes and (optionally) rendered labels for the nodes and
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/// edges, as well as an identifier for the graph itself.
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pub trait Labeller<'a,N,E> {
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/// Must return a DOT compatible identifier naming the graph.
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fn graph_id(&'a self) -> Id<'a>;
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/// Maps `n` to a unique identifier with respect to `self`. The
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/// implementer is responsible for ensuring that the returned name
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/// is a valid DOT identifier.
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fn node_id(&'a self, n: &N) -> Id<'a>;
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/// Maps `n` to a label that will be used in the rendered output.
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/// The label need not be unique, and may be the empty string; the
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/// default is just the output from `node_id`.
|
|
fn node_label(&'a self, n: &N) -> LabelText<'a> {
|
|
LabelStr(self.node_id(n).name)
|
|
}
|
|
|
|
/// Maps `e` to a label that will be used in the rendered output.
|
|
/// The label need not be unique, and may be the empty string; the
|
|
/// default is in fact the empty string.
|
|
fn edge_label(&'a self, e: &E) -> LabelText<'a> {
|
|
let _ignored = e;
|
|
LabelStr("".into_cow())
|
|
}
|
|
}
|
|
|
|
impl<'a> LabelText<'a> {
|
|
pub fn label<S:IntoCow<'a, str>>(s: S) -> LabelText<'a> {
|
|
LabelStr(s.into_cow())
|
|
}
|
|
|
|
pub fn escaped<S:IntoCow<'a, str>>(s: S) -> LabelText<'a> {
|
|
EscStr(s.into_cow())
|
|
}
|
|
|
|
fn escape_char<F>(c: char, mut f: F) where F: FnMut(char) {
|
|
match c {
|
|
// not escaping \\, since Graphviz escString needs to
|
|
// interpret backslashes; see EscStr above.
|
|
'\\' => f(c),
|
|
_ => for c in c.escape_default() { f(c) }
|
|
}
|
|
}
|
|
fn escape_str(s: &str) -> String {
|
|
let mut out = String::with_capacity(s.len());
|
|
for c in s.chars() {
|
|
LabelText::escape_char(c, |c| out.push(c));
|
|
}
|
|
out
|
|
}
|
|
|
|
/// Renders text as string suitable for a label in a .dot file.
|
|
pub fn escape(&self) -> String {
|
|
match self {
|
|
&LabelStr(ref s) => s.escape_default(),
|
|
&EscStr(ref s) => LabelText::escape_str(&s[..]),
|
|
}
|
|
}
|
|
|
|
/// Decomposes content into string suitable for making EscStr that
|
|
/// yields same content as self. The result obeys the law
|
|
/// render(`lt`) == render(`EscStr(lt.pre_escaped_content())`) for
|
|
/// all `lt: LabelText`.
|
|
fn pre_escaped_content(self) -> Cow<'a, str> {
|
|
match self {
|
|
EscStr(s) => s,
|
|
LabelStr(s) => if s.contains('\\') {
|
|
(&*s).escape_default().into_cow()
|
|
} else {
|
|
s
|
|
},
|
|
}
|
|
}
|
|
|
|
/// Puts `prefix` on a line above this label, with a blank line separator.
|
|
pub fn prefix_line(self, prefix: LabelText) -> LabelText<'static> {
|
|
prefix.suffix_line(self)
|
|
}
|
|
|
|
/// Puts `suffix` on a line below this label, with a blank line separator.
|
|
pub fn suffix_line(self, suffix: LabelText) -> LabelText<'static> {
|
|
let mut prefix = self.pre_escaped_content().into_owned();
|
|
let suffix = suffix.pre_escaped_content();
|
|
prefix.push_str(r"\n\n");
|
|
prefix.push_str(&suffix[..]);
|
|
EscStr(prefix.into_cow())
|
|
}
|
|
}
|
|
|
|
pub type Nodes<'a,N> = Cow<'a,[N]>;
|
|
pub type Edges<'a,E> = Cow<'a,[E]>;
|
|
|
|
// (The type parameters in GraphWalk should be associated items,
|
|
// when/if Rust supports such.)
|
|
|
|
/// GraphWalk is an abstraction over a directed graph = (nodes,edges)
|
|
/// made up of node handles `N` and edge handles `E`, where each `E`
|
|
/// can be mapped to its source and target nodes.
|
|
///
|
|
/// The lifetime parameter `'a` is exposed in this trait (rather than
|
|
/// introduced as a generic parameter on each method declaration) so
|
|
/// that a client impl can choose `N` and `E` that have substructure
|
|
/// that is bound by the self lifetime `'a`.
|
|
///
|
|
/// The `nodes` and `edges` method each return instantiations of
|
|
/// `Cow<[T]>` to leave implementers the freedom to create
|
|
/// entirely new vectors or to pass back slices into internally owned
|
|
/// vectors.
|
|
pub trait GraphWalk<'a, N, E> {
|
|
/// Returns all the nodes in this graph.
|
|
fn nodes(&'a self) -> Nodes<'a, N>;
|
|
/// Returns all of the edges in this graph.
|
|
fn edges(&'a self) -> Edges<'a, E>;
|
|
/// The source node for `edge`.
|
|
fn source(&'a self, edge: &E) -> N;
|
|
/// The target node for `edge`.
|
|
fn target(&'a self, edge: &E) -> N;
|
|
}
|
|
|
|
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
|
|
pub enum RenderOption {
|
|
NoEdgeLabels,
|
|
NoNodeLabels,
|
|
}
|
|
|
|
/// Returns vec holding all the default render options.
|
|
pub fn default_options() -> Vec<RenderOption> { vec![] }
|
|
|
|
/// Renders directed graph `g` into the writer `w` in DOT syntax.
|
|
/// (Simple wrapper around `render_opts` that passes a default set of options.)
|
|
pub fn render<'a, N:Clone+'a, E:Clone+'a, G:Labeller<'a,N,E>+GraphWalk<'a,N,E>, W:Write>(
|
|
g: &'a G,
|
|
w: &mut W) -> io::Result<()> {
|
|
render_opts(g, w, &[])
|
|
}
|
|
|
|
/// Renders directed graph `g` into the writer `w` in DOT syntax.
|
|
/// (Main entry point for the library.)
|
|
pub fn render_opts<'a, N:Clone+'a, E:Clone+'a, G:Labeller<'a,N,E>+GraphWalk<'a,N,E>, W:Write>(
|
|
g: &'a G,
|
|
w: &mut W,
|
|
options: &[RenderOption]) -> io::Result<()>
|
|
{
|
|
fn writeln<W:Write>(w: &mut W, arg: &[&str]) -> io::Result<()> {
|
|
for &s in arg { try!(w.write_all(s.as_bytes())); }
|
|
write!(w, "\n")
|
|
}
|
|
|
|
fn indent<W:Write>(w: &mut W) -> io::Result<()> {
|
|
w.write_all(b" ")
|
|
}
|
|
|
|
try!(writeln(w, &["digraph ", g.graph_id().as_slice(), " {"]));
|
|
for n in g.nodes().iter() {
|
|
try!(indent(w));
|
|
let id = g.node_id(n);
|
|
if options.contains(&RenderOption::NoNodeLabels) {
|
|
try!(writeln(w, &[id.as_slice(), ";"]));
|
|
} else {
|
|
let escaped = g.node_label(n).escape();
|
|
try!(writeln(w, &[id.as_slice(),
|
|
"[label=\"", &escaped, "\"];"]));
|
|
}
|
|
}
|
|
|
|
for e in g.edges().iter() {
|
|
let escaped_label = g.edge_label(e).escape();
|
|
try!(indent(w));
|
|
let source = g.source(e);
|
|
let target = g.target(e);
|
|
let source_id = g.node_id(&source);
|
|
let target_id = g.node_id(&target);
|
|
if options.contains(&RenderOption::NoEdgeLabels) {
|
|
try!(writeln(w, &[source_id.as_slice(),
|
|
" -> ", target_id.as_slice(), ";"]));
|
|
} else {
|
|
try!(writeln(w, &[source_id.as_slice(),
|
|
" -> ", target_id.as_slice(),
|
|
"[label=\"", &escaped_label, "\"];"]));
|
|
}
|
|
}
|
|
|
|
writeln(w, &["}"])
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use self::NodeLabels::*;
|
|
use super::{Id, Labeller, Nodes, Edges, GraphWalk, render};
|
|
use super::LabelText::{self, LabelStr, EscStr};
|
|
use std::io;
|
|
use std::io::prelude::*;
|
|
use std::borrow::IntoCow;
|
|
|
|
/// each node is an index in a vector in the graph.
|
|
type Node = usize;
|
|
struct Edge {
|
|
from: usize, to: usize, label: &'static str
|
|
}
|
|
|
|
fn edge(from: usize, to: usize, label: &'static str) -> Edge {
|
|
Edge { from: from, to: to, label: label }
|
|
}
|
|
|
|
struct LabelledGraph {
|
|
/// The name for this graph. Used for labelling generated `digraph`.
|
|
name: &'static str,
|
|
|
|
/// Each node is an index into `node_labels`; these labels are
|
|
/// used as the label text for each node. (The node *names*,
|
|
/// which are unique identifiers, are derived from their index
|
|
/// in this array.)
|
|
///
|
|
/// If a node maps to None here, then just use its name as its
|
|
/// text.
|
|
node_labels: Vec<Option<&'static str>>,
|
|
|
|
/// Each edge relates a from-index to a to-index along with a
|
|
/// label; `edges` collects them.
|
|
edges: Vec<Edge>,
|
|
}
|
|
|
|
// A simple wrapper around LabelledGraph that forces the labels to
|
|
// be emitted as EscStr.
|
|
struct LabelledGraphWithEscStrs {
|
|
graph: LabelledGraph
|
|
}
|
|
|
|
enum NodeLabels<L> {
|
|
AllNodesLabelled(Vec<L>),
|
|
UnlabelledNodes(usize),
|
|
SomeNodesLabelled(Vec<Option<L>>),
|
|
}
|
|
|
|
type Trivial = NodeLabels<&'static str>;
|
|
|
|
impl NodeLabels<&'static str> {
|
|
fn to_opt_strs(self) -> Vec<Option<&'static str>> {
|
|
match self {
|
|
UnlabelledNodes(len)
|
|
=> vec![None; len],
|
|
AllNodesLabelled(lbls)
|
|
=> lbls.into_iter().map(
|
|
|l|Some(l)).collect(),
|
|
SomeNodesLabelled(lbls)
|
|
=> lbls.into_iter().collect(),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl LabelledGraph {
|
|
fn new(name: &'static str,
|
|
node_labels: Trivial,
|
|
edges: Vec<Edge>) -> LabelledGraph {
|
|
LabelledGraph {
|
|
name: name,
|
|
node_labels: node_labels.to_opt_strs(),
|
|
edges: edges
|
|
}
|
|
}
|
|
}
|
|
|
|
impl LabelledGraphWithEscStrs {
|
|
fn new(name: &'static str,
|
|
node_labels: Trivial,
|
|
edges: Vec<Edge>) -> LabelledGraphWithEscStrs {
|
|
LabelledGraphWithEscStrs {
|
|
graph: LabelledGraph::new(name, node_labels, edges)
|
|
}
|
|
}
|
|
}
|
|
|
|
fn id_name<'a>(n: &Node) -> Id<'a> {
|
|
Id::new(format!("N{}", *n)).unwrap()
|
|
}
|
|
|
|
impl<'a> Labeller<'a, Node, &'a Edge> for LabelledGraph {
|
|
fn graph_id(&'a self) -> Id<'a> {
|
|
Id::new(&self.name[..]).unwrap()
|
|
}
|
|
fn node_id(&'a self, n: &Node) -> Id<'a> {
|
|
id_name(n)
|
|
}
|
|
fn node_label(&'a self, n: &Node) -> LabelText<'a> {
|
|
match self.node_labels[*n] {
|
|
Some(ref l) => LabelStr(l.into_cow()),
|
|
None => LabelStr(id_name(n).name()),
|
|
}
|
|
}
|
|
fn edge_label(&'a self, e: & &'a Edge) -> LabelText<'a> {
|
|
LabelStr(e.label.into_cow())
|
|
}
|
|
}
|
|
|
|
impl<'a> Labeller<'a, Node, &'a Edge> for LabelledGraphWithEscStrs {
|
|
fn graph_id(&'a self) -> Id<'a> { self.graph.graph_id() }
|
|
fn node_id(&'a self, n: &Node) -> Id<'a> { self.graph.node_id(n) }
|
|
fn node_label(&'a self, n: &Node) -> LabelText<'a> {
|
|
match self.graph.node_label(n) {
|
|
LabelStr(s) | EscStr(s) => EscStr(s),
|
|
}
|
|
}
|
|
fn edge_label(&'a self, e: & &'a Edge) -> LabelText<'a> {
|
|
match self.graph.edge_label(e) {
|
|
LabelStr(s) | EscStr(s) => EscStr(s),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'a> GraphWalk<'a, Node, &'a Edge> for LabelledGraph {
|
|
fn nodes(&'a self) -> Nodes<'a,Node> {
|
|
(0..self.node_labels.len()).collect()
|
|
}
|
|
fn edges(&'a self) -> Edges<'a,&'a Edge> {
|
|
self.edges.iter().collect()
|
|
}
|
|
fn source(&'a self, edge: & &'a Edge) -> Node {
|
|
edge.from
|
|
}
|
|
fn target(&'a self, edge: & &'a Edge) -> Node {
|
|
edge.to
|
|
}
|
|
}
|
|
|
|
impl<'a> GraphWalk<'a, Node, &'a Edge> for LabelledGraphWithEscStrs {
|
|
fn nodes(&'a self) -> Nodes<'a,Node> {
|
|
self.graph.nodes()
|
|
}
|
|
fn edges(&'a self) -> Edges<'a,&'a Edge> {
|
|
self.graph.edges()
|
|
}
|
|
fn source(&'a self, edge: & &'a Edge) -> Node {
|
|
edge.from
|
|
}
|
|
fn target(&'a self, edge: & &'a Edge) -> Node {
|
|
edge.to
|
|
}
|
|
}
|
|
|
|
fn test_input(g: LabelledGraph) -> io::Result<String> {
|
|
let mut writer = Vec::new();
|
|
render(&g, &mut writer).unwrap();
|
|
let mut s = String::new();
|
|
try!(Read::read_to_string(&mut &*writer, &mut s));
|
|
Ok(s)
|
|
}
|
|
|
|
// All of the tests use raw-strings as the format for the expected outputs,
|
|
// so that you can cut-and-paste the content into a .dot file yourself to
|
|
// see what the graphviz visualizer would produce.
|
|
|
|
#[test]
|
|
fn empty_graph() {
|
|
let labels : Trivial = UnlabelledNodes(0);
|
|
let r = test_input(LabelledGraph::new("empty_graph", labels, vec!()));
|
|
assert_eq!(r.unwrap(),
|
|
r#"digraph empty_graph {
|
|
}
|
|
"#);
|
|
}
|
|
|
|
#[test]
|
|
fn single_node() {
|
|
let labels : Trivial = UnlabelledNodes(1);
|
|
let r = test_input(LabelledGraph::new("single_node", labels, vec!()));
|
|
assert_eq!(r.unwrap(),
|
|
r#"digraph single_node {
|
|
N0[label="N0"];
|
|
}
|
|
"#);
|
|
}
|
|
|
|
#[test]
|
|
fn single_edge() {
|
|
let labels : Trivial = UnlabelledNodes(2);
|
|
let result = test_input(LabelledGraph::new("single_edge", labels,
|
|
vec!(edge(0, 1, "E"))));
|
|
assert_eq!(result.unwrap(),
|
|
r#"digraph single_edge {
|
|
N0[label="N0"];
|
|
N1[label="N1"];
|
|
N0 -> N1[label="E"];
|
|
}
|
|
"#);
|
|
}
|
|
|
|
#[test]
|
|
fn test_some_labelled() {
|
|
let labels : Trivial = SomeNodesLabelled(vec![Some("A"), None]);
|
|
let result = test_input(LabelledGraph::new("test_some_labelled", labels,
|
|
vec![edge(0, 1, "A-1")]));
|
|
assert_eq!(result.unwrap(),
|
|
r#"digraph test_some_labelled {
|
|
N0[label="A"];
|
|
N1[label="N1"];
|
|
N0 -> N1[label="A-1"];
|
|
}
|
|
"#);
|
|
}
|
|
|
|
#[test]
|
|
fn single_cyclic_node() {
|
|
let labels : Trivial = UnlabelledNodes(1);
|
|
let r = test_input(LabelledGraph::new("single_cyclic_node", labels,
|
|
vec!(edge(0, 0, "E"))));
|
|
assert_eq!(r.unwrap(),
|
|
r#"digraph single_cyclic_node {
|
|
N0[label="N0"];
|
|
N0 -> N0[label="E"];
|
|
}
|
|
"#);
|
|
}
|
|
|
|
#[test]
|
|
fn hasse_diagram() {
|
|
let labels = AllNodesLabelled(vec!("{x,y}", "{x}", "{y}", "{}"));
|
|
let r = test_input(LabelledGraph::new(
|
|
"hasse_diagram", labels,
|
|
vec!(edge(0, 1, ""), edge(0, 2, ""),
|
|
edge(1, 3, ""), edge(2, 3, ""))));
|
|
assert_eq!(r.unwrap(),
|
|
r#"digraph hasse_diagram {
|
|
N0[label="{x,y}"];
|
|
N1[label="{x}"];
|
|
N2[label="{y}"];
|
|
N3[label="{}"];
|
|
N0 -> N1[label=""];
|
|
N0 -> N2[label=""];
|
|
N1 -> N3[label=""];
|
|
N2 -> N3[label=""];
|
|
}
|
|
"#);
|
|
}
|
|
|
|
#[test]
|
|
fn left_aligned_text() {
|
|
let labels = AllNodesLabelled(vec!(
|
|
"if test {\
|
|
\\l branch1\
|
|
\\l} else {\
|
|
\\l branch2\
|
|
\\l}\
|
|
\\lafterward\
|
|
\\l",
|
|
"branch1",
|
|
"branch2",
|
|
"afterward"));
|
|
|
|
let mut writer = Vec::new();
|
|
|
|
let g = LabelledGraphWithEscStrs::new(
|
|
"syntax_tree", labels,
|
|
vec!(edge(0, 1, "then"), edge(0, 2, "else"),
|
|
edge(1, 3, ";"), edge(2, 3, ";" )));
|
|
|
|
render(&g, &mut writer).unwrap();
|
|
let mut r = String::new();
|
|
Read::read_to_string(&mut &*writer, &mut r).unwrap();
|
|
|
|
assert_eq!(r,
|
|
r#"digraph syntax_tree {
|
|
N0[label="if test {\l branch1\l} else {\l branch2\l}\lafterward\l"];
|
|
N1[label="branch1"];
|
|
N2[label="branch2"];
|
|
N3[label="afterward"];
|
|
N0 -> N1[label="then"];
|
|
N0 -> N2[label="else"];
|
|
N1 -> N3[label=";"];
|
|
N2 -> N3[label=";"];
|
|
}
|
|
"#);
|
|
}
|
|
|
|
#[test]
|
|
fn simple_id_construction() {
|
|
let id1 = Id::new("hello");
|
|
match id1 {
|
|
Ok(_) => {;},
|
|
Err(..) => panic!("'hello' is not a valid value for id anymore")
|
|
}
|
|
}
|
|
|
|
#[test]
|
|
fn badly_formatted_id() {
|
|
let id2 = Id::new("Weird { struct : ure } !!!");
|
|
match id2 {
|
|
Ok(_) => panic!("graphviz id suddenly allows spaces, brackets and stuff"),
|
|
Err(..) => {;}
|
|
}
|
|
}
|
|
}
|