// Copyright 2014 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. //! Generate files suitable for use with [Graphviz](http://www.graphviz.org/) //! //! The `render` function generates output (e.g. an `output.dot` file) for //! use with [Graphviz](http://www.graphviz.org/) by walking a labelled //! graph. (Graphviz can then automatically lay out the nodes and edges //! of the graph, and also optionally render the graph as an image or //! other [output formats]( //! http://www.graphviz.org/content/output-formats), such as SVG.) //! //! Rather than impose some particular graph data structure on clients, //! this library exposes two traits that clients can implement on their //! own structs before handing them over to the rendering function. //! //! Note: This library does not yet provide access to the full //! expressiveness of the [DOT language]( //! http://www.graphviz.org/doc/info/lang.html). For example, there are //! many [attributes](http://www.graphviz.org/content/attrs) related to //! providing layout hints (e.g. left-to-right versus top-down, which //! algorithm to use, etc). The current intention of this library is to //! emit a human-readable .dot file with very regular structure suitable //! for easy post-processing. //! //! # Examples //! //! The first example uses a very simple graph representation: a list of //! pairs of ints, representing the edges (the node set is implicit). //! Each node label is derived directly from the int representing the node, //! while the edge labels are all empty strings. //! //! This example also illustrates how to use `CowVec` to return //! an owned vector or a borrowed slice as appropriate: we construct the //! node vector from scratch, but borrow the edge list (rather than //! constructing a copy of all the edges from scratch). //! //! The output from this example renders five nodes, with the first four //! forming a diamond-shaped acyclic graph and then pointing to the fifth //! which is cyclic. //! //! ```rust //! use std::borrow::IntoCow; //! use graphviz as dot; //! //! type Nd = int; //! type Ed = (int,int); //! struct Edges(Vec); //! //! pub fn render_to(output: &mut W) { //! let edges = Edges(vec!((0,1), (0,2), (1,3), (2,3), (3,4), (4,4))); //! dot::render(&edges, output).unwrap() //! } //! //! impl<'a> dot::Labeller<'a, Nd, Ed> for Edges { //! fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new("example1").unwrap() } //! //! fn node_id(&'a self, n: &Nd) -> dot::Id<'a> { //! dot::Id::new(format!("N{}", *n)).unwrap() //! } //! } //! //! impl<'a> dot::GraphWalk<'a, Nd, Ed> for Edges { //! fn nodes(&self) -> dot::Nodes<'a,Nd> { //! // (assumes that |N| \approxeq |E|) //! let &Edges(ref v) = self; //! let mut nodes = Vec::with_capacity(v.len()); //! for &(s,t) in v.iter() { //! nodes.push(s); nodes.push(t); //! } //! nodes.sort(); //! nodes.dedup(); //! nodes.into_cow() //! } //! //! fn edges(&'a self) -> dot::Edges<'a,Ed> { //! let &Edges(ref edges) = self; //! edges.as_slice().into_cow() //! } //! //! fn source(&self, e: &Ed) -> Nd { let &(s,_) = e; s } //! //! fn target(&self, e: &Ed) -> Nd { let &(_,t) = e; t } //! } //! //! # pub fn main() { render_to(&mut Vec::new()) } //! ``` //! //! ```no_run //! # pub fn render_to(output: &mut W) { unimplemented!() } //! pub fn main() { //! use std::old_io::File; //! let mut f = File::create(&Path::new("example1.dot")); //! render_to(&mut f) //! } //! ``` //! //! Output from first example (in `example1.dot`): //! //! ```ignore //! digraph example1 { //! N0[label="N0"]; //! N1[label="N1"]; //! N2[label="N2"]; //! N3[label="N3"]; //! N4[label="N4"]; //! N0 -> N1[label=""]; //! N0 -> N2[label=""]; //! N1 -> N3[label=""]; //! N2 -> N3[label=""]; //! N3 -> N4[label=""]; //! N4 -> N4[label=""]; //! } //! ``` //! //! The second example illustrates using `node_label` and `edge_label` to //! add labels to the nodes and edges in the rendered graph. The graph //! here carries both `nodes` (the label text to use for rendering a //! particular node), and `edges` (again a list of `(source,target)` //! indices). //! //! This example also illustrates how to use a type (in this case the edge //! type) that shares substructure with the graph: the edge type here is a //! direct reference to the `(source,target)` pair stored in the graph's //! internal vector (rather than passing around a copy of the pair //! itself). Note that this implies that `fn edges(&'a self)` must //! construct a fresh `Vec<&'a (uint,uint)>` from the `Vec<(uint,uint)>` //! edges stored in `self`. //! //! Since both the set of nodes and the set of edges are always //! constructed from scratch via iterators, we use the `collect()` method //! from the `Iterator` trait to collect the nodes and edges into freshly //! constructed growable `Vec` values (rather use the `into_cow` //! from the `IntoCow` trait as was used in the first example //! above). //! //! The output from this example renders four nodes that make up the //! Hasse-diagram for the subsets of the set `{x, y}`. Each edge is //! labelled with the ⊆ character (specified using the HTML character //! entity `&sube`). //! //! ```rust //! use std::borrow::IntoCow; //! use graphviz as dot; //! //! type Nd = uint; //! type Ed<'a> = &'a (uint, uint); //! struct Graph { nodes: Vec<&'static str>, edges: Vec<(uint,uint)> } //! //! pub fn render_to(output: &mut W) { //! let nodes = vec!("{x,y}","{x}","{y}","{}"); //! let edges = vec!((0,1), (0,2), (1,3), (2,3)); //! let graph = Graph { nodes: nodes, edges: edges }; //! //! dot::render(&graph, output).unwrap() //! } //! //! impl<'a> dot::Labeller<'a, Nd, Ed<'a>> for Graph { //! fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new("example2").unwrap() } //! fn node_id(&'a self, n: &Nd) -> dot::Id<'a> { //! dot::Id::new(format!("N{}", n)).unwrap() //! } //! fn node_label<'b>(&'b self, n: &Nd) -> dot::LabelText<'b> { //! dot::LabelText::LabelStr(self.nodes[*n].as_slice().into_cow()) //! } //! fn edge_label<'b>(&'b self, _: &Ed) -> dot::LabelText<'b> { //! dot::LabelText::LabelStr("⊆".into_cow()) //! } //! } //! //! impl<'a> dot::GraphWalk<'a, Nd, Ed<'a>> for Graph { //! fn nodes(&self) -> dot::Nodes<'a,Nd> { (0..self.nodes.len()).collect() } //! fn edges(&'a self) -> dot::Edges<'a,Ed<'a>> { self.edges.iter().collect() } //! fn source(&self, e: &Ed) -> Nd { let & &(s,_) = e; s } //! fn target(&self, e: &Ed) -> Nd { let & &(_,t) = e; t } //! } //! //! # pub fn main() { render_to(&mut Vec::new()) } //! ``` //! //! ```no_run //! # pub fn render_to(output: &mut W) { unimplemented!() } //! pub fn main() { //! use std::old_io::File; //! let mut f = File::create(&Path::new("example2.dot")); //! render_to(&mut f) //! } //! ``` //! //! The third example is similar to the second, except now each node and //! edge now carries a reference to the string label for each node as well //! as that node's index. (This is another illustration of how to share //! structure with the graph itself, and why one might want to do so.) //! //! The output from this example is the same as the second example: the //! Hasse-diagram for the subsets of the set `{x, y}`. //! //! ```rust //! use std::borrow::IntoCow; //! use graphviz as dot; //! //! type Nd<'a> = (uint, &'a str); //! type Ed<'a> = (Nd<'a>, Nd<'a>); //! struct Graph { nodes: Vec<&'static str>, edges: Vec<(uint,uint)> } //! //! pub fn render_to(output: &mut W) { //! let nodes = vec!("{x,y}","{x}","{y}","{}"); //! let edges = vec!((0,1), (0,2), (1,3), (2,3)); //! let graph = Graph { nodes: nodes, edges: edges }; //! //! dot::render(&graph, output).unwrap() //! } //! //! impl<'a> dot::Labeller<'a, Nd<'a>, Ed<'a>> for Graph { //! fn graph_id(&'a self) -> dot::Id<'a> { dot::Id::new("example3").unwrap() } //! fn node_id(&'a self, n: &Nd<'a>) -> dot::Id<'a> { //! dot::Id::new(format!("N{}", n.0)).unwrap() //! } //! fn node_label<'b>(&'b self, n: &Nd<'b>) -> dot::LabelText<'b> { //! let &(i, _) = n; //! dot::LabelText::LabelStr(self.nodes[i].as_slice().into_cow()) //! } //! fn edge_label<'b>(&'b self, _: &Ed<'b>) -> dot::LabelText<'b> { //! dot::LabelText::LabelStr("⊆".into_cow()) //! } //! } //! //! impl<'a> dot::GraphWalk<'a, Nd<'a>, Ed<'a>> for Graph { //! fn nodes(&'a self) -> dot::Nodes<'a,Nd<'a>> { //! self.nodes.iter().map(|s|s.as_slice()).enumerate().collect() //! } //! fn edges(&'a self) -> dot::Edges<'a,Ed<'a>> { //! self.edges.iter() //! .map(|&(i,j)|((i, self.nodes[i].as_slice()), //! (j, self.nodes[j].as_slice()))) //! .collect() //! } //! fn source(&self, e: &Ed<'a>) -> Nd<'a> { let &(s,_) = e; s } //! fn target(&self, e: &Ed<'a>) -> Nd<'a> { let &(_,t) = e; t } //! } //! //! # pub fn main() { render_to(&mut Vec::new()) } //! ``` //! //! ```no_run //! # pub fn render_to(output: &mut W) { unimplemented!() } //! pub fn main() { //! use std::old_io::File; //! let mut f = File::create(&Path::new("example3.dot")); //! render_to(&mut f) //! } //! ``` //! //! # References //! //! * [Graphviz](http://www.graphviz.org/) //! //! * [DOT language](http://www.graphviz.org/doc/info/lang.html) #![crate_name = "graphviz"] #![unstable(feature = "rustc_private")] #![feature(staged_api)] #![staged_api] #![crate_type = "rlib"] #![crate_type = "dylib"] #![doc(html_logo_url = "http://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png", html_favicon_url = "http://www.rust-lang.org/favicon.ico", html_root_url = "http://doc.rust-lang.org/nightly/")] #![feature(slicing_syntax)] #![feature(int_uint)] #![feature(collections)] #![feature(core)] #![feature(io)] #![feature(path)] use self::LabelText::*; use std::borrow::IntoCow; use std::old_io; use std::string::CowString; use std::vec::CowVec; pub mod maybe_owned_vec; /// The text for a graphviz label on a node or edge. pub enum LabelText<'a> { /// This kind of label preserves the text directly as is. /// /// Occurrences of backslashes (`\`) are escaped, and thus appear /// as backslashes in the rendered label. LabelStr(CowString<'a>), /// This kind of label uses the graphviz label escString type: /// http://www.graphviz.org/content/attrs#kescString /// /// Occurrences of backslashes (`\`) are not escaped; instead they /// are interpreted as initiating an escString escape sequence. /// /// Escape sequences of particular interest: in addition to `\n` /// to break a line (centering the line preceding the `\n`), there /// are also the escape sequences `\l` which left-justifies the /// preceding line and `\r` which right-justifies it. EscStr(CowString<'a>), } // There is a tension in the design of the labelling API. // // For example, I considered making a `Labeller` trait that // provides labels for `T`, and then making the graph type `G` // implement `Labeller` and `Labeller`. However, this is // not possible without functional dependencies. (One could work // around that, but I did not explore that avenue heavily.) // // Another approach that I actually used for a while was to make a // `Label` trait that is implemented by the client-specific // Node and Edge types (as well as an implementation on Graph itself // for the overall name for the graph). The main disadvantage of this // second approach (compared to having the `G` type parameter // implement a Labelling service) that I have encountered is that it // makes it impossible to use types outside of the current crate // directly as Nodes/Edges; you need to wrap them in newtype'd // structs. See e.g. the `No` and `Ed` structs in the examples. (In // practice clients using a graph in some other crate would need to // provide some sort of adapter shim over the graph anyway to // interface with this library). // // Another approach would be to make a single `Labeller` trait // that provides three methods (graph_label, node_label, edge_label), // and then make `G` implement `Labeller`. At first this did not // appeal to me, since I had thought I would need separate methods on // each data variant for dot-internal identifiers versus user-visible // labels. However, the identifier/label distinction only arises for // nodes; graphs themselves only have identifiers, and edges only have // labels. // // So in the end I decided to use the third approach described above. /// `Id` is a Graphviz `ID`. pub struct Id<'a> { name: CowString<'a>, } impl<'a> Id<'a> { /// Creates an `Id` named `name`. /// /// The caller must ensure that the input conforms to an /// identifier format: it must be a non-empty string made up of /// alphanumeric or underscore characters, not beginning with a /// digit (i.e. the regular expression `[a-zA-Z_][a-zA-Z_0-9]*`). /// /// (Note: this format is a strict subset of the `ID` format /// defined by the DOT language. This function may change in the /// future to accept a broader subset, or the entirety, of DOT's /// `ID` format.) /// /// Passing an invalid string (containing spaces, brackets, /// quotes, ...) will return an empty `Err` value. pub fn new>(name: Name) -> Result, ()> { let name = name.into_cow(); { let mut chars = name.chars(); match chars.next() { Some(c) if is_letter_or_underscore(c) => { ; }, _ => return Err(()) } if !chars.all(is_constituent) { return Err(()) } } return Ok(Id{ name: name }); fn is_letter_or_underscore(c: char) -> bool { in_range('a', c, 'z') || in_range('A', c, 'Z') || c == '_' } fn is_constituent(c: char) -> bool { is_letter_or_underscore(c) || in_range('0', c, '9') } fn in_range(low: char, c: char, high: char) -> bool { low as uint <= c as uint && c as uint <= high as uint } } pub fn as_slice(&'a self) -> &'a str { &*self.name } pub fn name(self) -> CowString<'a> { self.name } } /// Each instance of a type that implements `Label` maps to a /// unique identifier with respect to `C`, which is used to identify /// it in the generated .dot file. They can also provide more /// elaborate (and non-unique) label text that is used in the graphviz /// rendered output. /// The graph instance is responsible for providing the DOT compatible /// identifiers for the nodes and (optionally) rendered labels for the nodes and /// edges, as well as an identifier for the graph itself. pub trait Labeller<'a,N,E> { /// Must return a DOT compatible identifier naming the graph. fn graph_id(&'a self) -> Id<'a>; /// Maps `n` to a unique identifier with respect to `self`. The /// implementer is responsible for ensuring that the returned name /// is a valid DOT identifier. fn node_id(&'a self, n: &N) -> Id<'a>; /// Maps `n` 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 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: S) -> LabelText<'a> { LabelStr(s.into_cow()) } pub fn escaped>(s: S) -> LabelText<'a> { EscStr(s.into_cow()) } fn escape_char(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) -> CowString<'a> { match self { EscStr(s) => s, LabelStr(s) => if s.contains_char('\\') { (&*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> = CowVec<'a,N>; pub type Edges<'a,E> = CowVec<'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 /// `CowVec` 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, PartialEq, Eq, Debug)] pub enum RenderOption { NoEdgeLabels, NoNodeLabels, } /// Returns vec holding all the default render options. pub fn default_options() -> Vec { 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:Writer>( g: &'a G, w: &mut W) -> old_io::IoResult<()> { 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:Writer>( g: &'a G, w: &mut W, options: &[RenderOption]) -> old_io::IoResult<()> { fn writeln(w: &mut W, arg: &[&str]) -> old_io::IoResult<()> { for &s in arg.iter() { try!(w.write_str(s)); } w.write_char('\n') } fn indent(w: &mut W) -> old_io::IoResult<()> { w.write_str(" ") } 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.as_slice(), "\"];"])); } } 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.as_slice(), "\"];"])); } } 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::old_io::IoResult; use std::borrow::IntoCow; use std::iter::repeat; /// each node is an index in a vector in the graph. type Node = uint; struct Edge { from: uint, to: uint, label: &'static str } fn edge(from: uint, to: uint, 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>, /// Each edge relates a from-index to a to-index along with a /// label; `edges` collects them. edges: Vec, } // A simple wrapper around LabelledGraph that forces the labels to // be emitted as EscStr. struct LabelledGraphWithEscStrs { graph: LabelledGraph } enum NodeLabels { AllNodesLabelled(Vec), UnlabelledNodes(uint), SomeNodesLabelled(Vec>), } type Trivial = NodeLabels<&'static str>; impl NodeLabels<&'static str> { fn to_opt_strs(self) -> Vec> { match self { UnlabelledNodes(len) => repeat(None).take(len).collect(), 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) -> 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) -> 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> { (0u..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) -> IoResult { let mut writer = Vec::new(); render(&g, &mut writer).unwrap(); (&mut writer.as_slice()).read_to_string() } // 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 r = (&mut writer.as_slice()).read_to_string(); assert_eq!(r.unwrap(), 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(..) => {;} } } }