Merge #1888

1888: allow compiling ra_ide_api on wasm r=matklad a=matklad

bors r+

this is from #1746 

Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>

crates/ra_ide_api/Cargo.toml

@@ -4,6 +4,9 @@ name = "ra_ide_api"
 version = "0.1.0"
 authors = ["rust-analyzer developers"]
 
+[features]
+wasm = []
+
 [dependencies]
 format-buf = "1.0.0"
 itertools = "0.8.0"

crates/ra_ide_api/src/change.rs

@@ -6,6 +6,7 @@
 };
 use ra_prof::{memory_usage, profile, Bytes};
 use ra_syntax::SourceFile;
+#[cfg(not(feature = "wasm"))]
 use rayon::prelude::*;
 use relative_path::RelativePathBuf;
 use rustc_hash::FxHashMap;
@@ -143,7 +144,12 @@ pub fn prepare(
         root_id: SourceRootId,
         files: Vec<(FileId, RelativePathBuf, Arc<String>)>,
     ) -> LibraryData {
-        let symbol_index = SymbolIndex::for_files(files.par_iter().map(|(file_id, _, text)| {
+        #[cfg(not(feature = "wasm"))]
+        let iter = files.par_iter();
+        #[cfg(feature = "wasm")]
+        let iter = files.iter();
+
+        let symbol_index = SymbolIndex::for_files(iter.map(|(file_id, _, text)| {
             let parse = SourceFile::parse(text);
             (*file_id, parse)
         }));
@@ -234,8 +240,12 @@ fn apply_root_change(&mut self, root_id: SourceRootId, root_change: RootChange)
     }
 
     pub(crate) fn maybe_collect_garbage(&mut self) {
+        if cfg!(feature = "wasm") {
+            return;
+        }
+
         if self.last_gc_check.elapsed() > GC_COOLDOWN {
-            self.last_gc_check = time::Instant::now();
+            self.last_gc_check = crate::wasm_shims::Instant::now();
             let retained_trees = syntax_tree_stats(self).retained;
             if retained_trees > 100 {
                 log::info!("automatic garbadge collection, {} retained trees", retained_trees);
@@ -245,8 +255,12 @@ pub(crate) fn maybe_collect_garbage(&mut self) {
     }
 
     pub(crate) fn collect_garbage(&mut self) {
+        if cfg!(feature = "wasm") {
+            return;
+        }
+
         let _p = profile("RootDatabase::collect_garbage");
-        self.last_gc = time::Instant::now();
+        self.last_gc = crate::wasm_shims::Instant::now();
 
         let sweep = SweepStrategy::default().discard_values().sweep_all_revisions();
 

crates/ra_ide_api/src/db.rs

@@ -1,4 +1,4 @@
-use std::{sync::Arc, time};
+use std::sync::Arc;
 
 use ra_db::{
     salsa::{self, Database, Durability},
@@ -25,8 +25,8 @@ pub(crate) struct RootDatabase {
     runtime: salsa::Runtime<RootDatabase>,
     pub(crate) feature_flags: Arc<FeatureFlags>,
     pub(crate) debug_data: Arc<DebugData>,
-    pub(crate) last_gc: time::Instant,
-    pub(crate) last_gc_check: time::Instant,
+    pub(crate) last_gc: crate::wasm_shims::Instant,
+    pub(crate) last_gc_check: crate::wasm_shims::Instant,
 }
 
 impl hir::debug::HirDebugHelper for RootDatabase {
@@ -69,8 +69,8 @@ impl RootDatabase {
     pub fn new(lru_capacity: Option<usize>, feature_flags: FeatureFlags) -> RootDatabase {
         let mut db = RootDatabase {
             runtime: salsa::Runtime::default(),
-            last_gc: time::Instant::now(),
-            last_gc_check: time::Instant::now(),
+            last_gc: crate::wasm_shims::Instant::now(),
+            last_gc_check: crate::wasm_shims::Instant::now(),
             feature_flags: Arc::new(feature_flags),
             debug_data: Default::default(),
         };

crates/ra_ide_api/src/lib.rs

@@ -40,6 +40,7 @@
 mod matching_brace;
 mod display;
 mod inlay_hints;
+mod wasm_shims;
 
 #[cfg(test)]
 mod marks;

crates/ra_ide_api/src/symbol_index.rs

@@ -38,6 +38,7 @@
     SyntaxKind::{self, *},
     SyntaxNode, SyntaxNodePtr, TextRange, WalkEvent,
 };
+#[cfg(not(feature = "wasm"))]
 use rayon::prelude::*;
 
 use crate::{db::RootDatabase, FileId, Query};
@@ -79,10 +80,17 @@ fn clone(&self) -> Snap {
 
     let buf: Vec<Arc<SymbolIndex>> = if query.libs {
         let snap = Snap(db.snapshot());
-        db.library_roots()
+        #[cfg(not(feature = "wasm"))]
+        let buf = db
+            .library_roots()
             .par_iter()
             .map_with(snap, |db, &lib_id| db.0.library_symbols(lib_id))
-            .collect()
+            .collect();
+
+        #[cfg(feature = "wasm")]
+        let buf = db.library_roots().iter().map(|&lib_id| snap.0.library_symbols(lib_id)).collect();
+
+        buf
     } else {
         let mut files = Vec::new();
         for &root in db.local_roots().iter() {
@@ -91,7 +99,14 @@ fn clone(&self) -> Snap {
         }
 
         let snap = Snap(db.snapshot());
-        files.par_iter().map_with(snap, |db, &file_id| db.0.file_symbols(file_id)).collect()
+        #[cfg(not(feature = "wasm"))]
+        let buf =
+            files.par_iter().map_with(snap, |db, &file_id| db.0.file_symbols(file_id)).collect();
+
+        #[cfg(feature = "wasm")]
+        let buf = files.iter().map(|&file_id| snap.0.file_symbols(file_id)).collect();
+
+        buf
     };
     query.search(&buf)
 }
@@ -135,9 +150,12 @@ fn new(mut symbols: Vec<FileSymbol>) -> SymbolIndex {
         fn cmp_key<'a>(s1: &'a FileSymbol) -> impl Ord + 'a {
             unicase::Ascii::new(s1.name.as_str())
         }
-
+        #[cfg(not(feature = "wasm"))]
         symbols.par_sort_by(|s1, s2| cmp_key(s1).cmp(&cmp_key(s2)));
 
+        #[cfg(feature = "wasm")]
+        symbols.sort_by(|s1, s2| cmp_key(s1).cmp(&cmp_key(s2)));
+
         let mut builder = fst::MapBuilder::memory();
 
         let mut last_batch_start = 0;
@@ -169,6 +187,7 @@ pub(crate) fn memory_size(&self) -> usize {
         self.map.as_fst().size() + self.symbols.len() * mem::size_of::<FileSymbol>()
     }
 
+    #[cfg(not(feature = "wasm"))]
     pub(crate) fn for_files(
         files: impl ParallelIterator<Item = (FileId, Parse<ast::SourceFile>)>,
     ) -> SymbolIndex {
@@ -178,6 +197,16 @@ pub(crate) fn for_files(
         SymbolIndex::new(symbols)
     }
 
+    #[cfg(feature = "wasm")]
+    pub(crate) fn for_files(
+        files: impl Iterator<Item = (FileId, Parse<ast::SourceFile>)>,
+    ) -> SymbolIndex {
+        let symbols = files
+            .flat_map(|(file_id, file)| source_file_to_file_symbols(&file.tree(), file_id))
+            .collect::<Vec<_>>();
+        SymbolIndex::new(symbols)
+    }
+
     fn range_to_map_value(start: usize, end: usize) -> u64 {
         debug_assert![start <= (std::u32::MAX as usize)];
         debug_assert![end <= (std::u32::MAX as usize)];

crates/ra_ide_api/src/wasm_shims.rs

@@ -0,0 +1,17 @@
+#[cfg(not(feature = "wasm"))]
+pub use std::time::Instant;
+
+#[cfg(feature = "wasm")]
+#[derive(Clone, Copy, Debug)]
+pub struct Instant;
+
+#[cfg(feature = "wasm")]
+impl Instant {
+    pub fn now() -> Self {
+        Self
+    }
+
+    pub fn elapsed(&self) -> std::time::Duration {
+        std::time::Duration::new(0, 0)
+    }
+}