Support for cancellation.

rbuckton · Aug 25, 2016 · 003802c · 003802c
1 parent 8b8b8d6
commit 003802c
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Showing 11 changed files with 98 additions and 20 deletions.
diff --git a/src/lib/binder.ts b/src/lib/binder.ts
@@ -13,6 +13,7 @@
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
  */
+import { CancellationToken } from "prex";
 import { Dictionary } from "./core";
 import { SyntaxKind } from "./tokens";
 import { Symbol, SymbolKind, SymbolTable } from "./symbols";
@@ -194,13 +195,16 @@ export class Binder {
     private parentSymbol: Symbol;
     private bindings: BindingTable;
     private scope: SymbolTable;
+    private cancellationToken: CancellationToken;
 
-    constructor(bindings: BindingTable) {
+    constructor(bindings: BindingTable, cancellationToken = CancellationToken.none) {
         this.bindings = bindings;
         this.scope = bindings.globals;
+        this.cancellationToken = cancellationToken;
     }
 
     public bindSourceFile(file: SourceFile): void {
+        this.cancellationToken.throwIfCancellationRequested();
         if (this.scope.resolveSymbol(file.filename, SymbolKind.SourceFile)) {
             // skip files that have already been bound.
             return;

diff --git a/src/lib/checker.ts b/src/lib/checker.ts
@@ -14,6 +14,7 @@
  *  limitations under the License.
  */
 import { Hash, createHash } from "crypto";
+import { CancellationToken } from "prex";
 import { Dictionary } from "./core";
 import { Diagnostics, DiagnosticMessages, Diagnostic, formatList } from "./diagnostics";
 import { SyntaxKind, tokenToString } from "./tokens";
@@ -73,11 +74,13 @@ export class Checker {
     private sourceFile: SourceFile;
     private noStrictParametricProductions: boolean;
     private productionParametersByName: Dictionary<Dictionary<boolean>>;
+    private cancellationToken: CancellationToken;
 
-    constructor(bindings: BindingTable, diagnostics: DiagnosticMessages, options?: CompilerOptions) {
+    constructor(bindings: BindingTable, diagnostics: DiagnosticMessages, options?: CompilerOptions, cancellationToken = CancellationToken.none) {
         this.bindings = bindings;
         this.diagnostics = diagnostics;
         this.noStrictParametricProductions = options && options.noStrictParametricProductions || false;
+        this.cancellationToken = cancellationToken;
     }
 
     public get resolver(): Resolver {
@@ -90,13 +93,12 @@ export class Checker {
 
     public checkSourceFile(sourceFile: SourceFile): void {
         if (!Dictionary.has(this.checkedFileSet, sourceFile.filename)) {
-            Dictionary.set(this.checkedFileSet, sourceFile.filename, true);
-            this.sourceFile = sourceFile;
+            const savedNoStrictParametricProductions = this.noStrictParametricProductions;
+            this.cancellationToken.throwIfCancellationRequested();
             this.productionParametersByName = new Dictionary<Dictionary<boolean>>();
+            this.sourceFile = sourceFile;
             this.diagnostics.setSourceFile(this.sourceFile);
 
-            const savedNoStrictParametricProductions = this.noStrictParametricProductions;
-
             for (const element of sourceFile.elements) {
                 this.preprocessSourceElement(element);
             }
@@ -105,9 +107,10 @@ export class Checker {
                 this.checkSourceElement(element);
             }
 
-            this.noStrictParametricProductions = savedNoStrictParametricProductions;
             this.sourceFile = undefined;
             this.productionParametersByName = undefined;
+            this.noStrictParametricProductions = savedNoStrictParametricProductions;
+            Dictionary.set(this.checkedFileSet, sourceFile.filename, true);
         }
     }
 

diff --git a/src/lib/emitter/emitter.ts b/src/lib/emitter/emitter.ts
@@ -1,5 +1,6 @@
 import * as fs from "fs";
 import * as path from "path";
+import { CancellationToken } from "prex";
 import { DiagnosticMessages } from "../diagnostics";
 import { CompilerOptions } from "../options";
 import { Checker, Resolver } from "../checker";
@@ -53,14 +54,17 @@ export class Emitter {
     private diagnostics: DiagnosticMessages;
     private sourceFile: SourceFile;
     private triviaPos: number;
+    private cancellationToken: CancellationToken;
 
-    constructor(options: CompilerOptions, resolver: Resolver, diagnostics: DiagnosticMessages) {
+    constructor(options: CompilerOptions, resolver: Resolver, diagnostics: DiagnosticMessages, cancellationToken = CancellationToken.none) {
         this.options = options;
         this.resolver = resolver;
         this.diagnostics = diagnostics;
+        this.cancellationToken = cancellationToken;
     }
 
     public emit(node: SourceFile, writeFile?: (file: string, text: string) => void): void {
+        this.cancellationToken.throwIfCancellationRequested();
         const saveWriter = this.writer;
         const saveSourceFile = this.sourceFile;
         const saveTriviaPos = this.triviaPos;

diff --git a/src/lib/grammar.ts b/src/lib/grammar.ts
@@ -12,12 +12,14 @@ import { Binder, BindingTable } from "./binder";
 import { Checker, Resolver } from "./checker";
 import { Emitter, EcmarkupEmitter, MarkdownEmitter, HtmlEmitter } from "./emitter/index";
 import { SourceFile, Import } from "./nodes";
+import { CancellationToken } from "prex";
 
 export class Grammar {
     public rootFiles: SourceFile[] = [];
     public sourceFiles: SourceFile[] = [];
     public options: CompilerOptions;
     public diagnostics: DiagnosticMessages = new DiagnosticMessages();
+    public readonly cancellationToken: CancellationToken;
 
     private static knownGrammars = new Dictionary<string>({
         "es6": require.resolve("../../grammars/es2015.grammar"),
@@ -39,12 +41,15 @@ export class Grammar {
 
     constructor(rootNames: string[]);
     constructor(rootNames: string[], options: CompilerOptions);
-    constructor(rootNames: string[], options: CompilerOptions, host: Host, oldGrammar?: Grammar);
+    constructor(rootNames: string[], options: CompilerOptions, host: Host, oldGrammar?: Grammar, token?: CancellationToken);
+    /*@obsolete*/
+    /*@internal*/
     constructor(rootNames: string[], options: CompilerOptions, readFile: (file: string) => string, oldGrammar?: Grammar);
-    constructor(rootNames: string[], options: CompilerOptions = getDefaultOptions(), readFileOrHostLike?: ((file: string) => string) | HostLike, oldGrammar?: Grammar) {
+    constructor(rootNames: string[], options: CompilerOptions = getDefaultOptions(), readFileOrHostLike?: ((file: string) => string) | HostLike, oldGrammar?: Grammar, token = CancellationToken.none) {
         this.host = Host.getHost(readFileOrHostLike);
         this.options = options;
         this.oldGrammar = oldGrammar;
+        this.cancellationToken = token;
         this.parse(rootNames);
         this.oldGrammar = undefined;
         Object.freeze(this.sourceFiles);
@@ -106,7 +111,9 @@ export class Grammar {
         performance.measure("parse", "beforeParse", "afterParse");
     }
 
-    /* @obsolete */ /* @internal */ bind(sourceFile: SourceFile): void;
+    /*@obsolete*/
+    /*@internal*/
+    bind(sourceFile: SourceFile): void;
 
     public bind(): void;
     public bind(sourceFile?: SourceFile) {
@@ -172,28 +179,28 @@ export class Grammar {
     }
 
     protected createParser(options: CompilerOptions): Parser {
-        return new Parser(this.diagnostics);
+        return new Parser(this.diagnostics, this.cancellationToken);
     }
 
     protected createBinder(options: CompilerOptions, bindings: BindingTable): Binder {
-        return new Binder(bindings);
+        return new Binder(bindings, this.cancellationToken);
     }
 
     protected createChecker(options: CompilerOptions, bindings: BindingTable): Checker {
-        return new Checker(bindings, options.noChecks ? NullDiagnosticMessages.instance : this.diagnostics);
+        return new Checker(bindings, options.noChecks ? NullDiagnosticMessages.instance : this.diagnostics, options, this.cancellationToken);
     }
 
     protected createEmitter(options: CompilerOptions, resolver: Resolver): Emitter {
         switch (options.format) {
             case EmitFormat.ecmarkup:
-                return new EcmarkupEmitter(options, resolver, this.diagnostics)
+                return new EcmarkupEmitter(options, resolver, this.diagnostics, this.cancellationToken)
 
             case EmitFormat.html:
-                return new HtmlEmitter(options, resolver, this.diagnostics);
+                return new HtmlEmitter(options, resolver, this.diagnostics, this.cancellationToken);
 
             case EmitFormat.markdown:
             default:
-                return new MarkdownEmitter(options, resolver, this.diagnostics);
+                return new MarkdownEmitter(options, resolver, this.diagnostics, this.cancellationToken);
         }
     }
 

diff --git a/src/lib/host.ts b/src/lib/host.ts
@@ -93,11 +93,16 @@ export namespace Host {
 
     export function getHost(): Host;
     export function getHost(hostLike: HostLike): Host;
+    /*@obsolete*/
+    /*@internal*/
     export function getHost(readFile: (file: string) => string): Host;
+    /*@obsolete*/
+    /*@internal*/
     export function getHost(readFileOrHostLike: ((file: string) => string) | HostLike): Host;
     export function getHost(readFileOrHostLike?: ((file: string) => string) | HostLike): Host {
         const host = getDefaultHost();
         if (typeof readFileOrHostLike === "function") {
+            console.warn(`Calling Host.getHost with a readFile function is an obsolete overload and will be removed in a future version.`);
             host.readFile = <(file: string) => string>readFileOrHostLike;
         }
         else if (typeof readFileOrHostLike === "object") {

diff --git a/src/lib/parser.ts b/src/lib/parser.ts
@@ -17,6 +17,7 @@ import { Range, Position, TextRange } from "./core";
 import { Diagnostics, DiagnosticMessages, NullDiagnosticMessages, LineMap, formatList } from "./diagnostics";
 import { SyntaxKind, tokenToString } from "./tokens";
 import { Scanner } from "./scanner";
+import { CancellationToken } from "prex";
 import {
     Node,
     StringLiteral,
@@ -115,9 +116,11 @@ export class Parser {
     private diagnostics: DiagnosticMessages;
     private parsingContext: ParsingContext;
     private previousSourceFile: SourceFile;
+    private cancellationToken: CancellationToken;
 
-    constructor(diagnostics: DiagnosticMessages) {
+    constructor(diagnostics: DiagnosticMessages, cancellationToken = CancellationToken.none) {
         this.diagnostics = diagnostics;
+        this.cancellationToken = cancellationToken;
     }
 
     // TODO(rbuckton): Incremental parser
@@ -155,7 +158,7 @@ export class Parser {
     private parse(filename: string, text: string, previousSourceFile: SourceFile, changeRange: TextRange) {
         this.sourceFile = new SourceFile(filename, text);
         this.diagnostics.setSourceFile(this.sourceFile);
-        this.scanner = new Scanner(filename, text, this.diagnostics);
+        this.scanner = new Scanner(filename, text, this.diagnostics, this.cancellationToken);
         this.parsingContext = ParsingContext.SourceElements;
 
         this.nextToken();
@@ -649,6 +652,7 @@ export class Parser {
         const whitespaceToSkip = this.shouldSkipWhitespace();
         let result: TNode[];
         while (!this.isEOF()) {
+            this.cancellationToken.throwIfCancellationRequested();
             this.skipWhitespace(whitespaceToSkip);
 
             let parsed = false;

diff --git a/src/lib/scanner.ts b/src/lib/scanner.ts
@@ -15,6 +15,7 @@
  */
 
 import { EOL } from 'os';
+import { CancellationToken } from "prex";
 import { TextRange } from "./core";
 import { CharacterCodes, SyntaxKind, stringToToken } from "./tokens";
 import { Diagnostics, Diagnostic, DiagnosticMessages, NullDiagnosticMessages } from "./diagnostics";
@@ -35,12 +36,14 @@ export class Scanner {
     private filename: string;
     private diagnostics: DiagnosticMessages;
     private proseStartToken: SyntaxKind;
+    private cancellationToken: CancellationToken;
 
-    constructor(filename: string, text: string, diagnostics: DiagnosticMessages) {
+    constructor(filename: string, text: string, diagnostics: DiagnosticMessages, cancellationToken = CancellationToken.none) {
         this.filename = filename;
         this.text = text;
         this.len = text.length;
         this.diagnostics = diagnostics;
+        this.cancellationToken = cancellationToken;
     }
 
     public getPos(): number {
@@ -76,6 +79,7 @@ export class Scanner {
     }
 
     public scan(): SyntaxKind {
+        this.cancellationToken.throwIfCancellationRequested();
         const token = this.dequeueOrScanToken();
         if (token === SyntaxKind.EndOfFileToken && this.indents.length) {
             for (let i = 0; i < this.indents.length; i++) {

diff --git a/src/tests/checker-tests.ts b/src/tests/checker-tests.ts
@@ -1,12 +1,24 @@
 import { basename } from "path";
 import { Grammar } from "../lib/grammar";
+import { Host } from "../lib/host";
 import { EmitFormat } from "../lib/options";
 import { getGrammarFiles } from "./resources";
 import { writeTokens, writeDiagnostics, writeOutput, compareBaseline } from "./diff";
+import { CancellationTokenSource } from "prex";
+import { assert } from "chai";
 
 describe("Checker", () => {
     defineTests();
 
+    it("cancelable", () => {
+        const cts = new CancellationTokenSource();
+        const grammar = new Grammar(["cancelable.grammar"], {}, Host.getHost({
+            readFile(file) { return ""; }
+        }), /*oldGrammar*/ undefined, cts.token);
+        cts.cancel();
+        assert.throws(() => grammar.check(/*sourceFile*/ undefined));
+    });
+
     function defineTests() {
         for (let file of getGrammarFiles()) {
             defineTest(basename(file), file);

diff --git a/src/tests/emitter-tests.ts b/src/tests/emitter-tests.ts
@@ -1,12 +1,26 @@
 import { basename } from "path";
 import { Grammar } from "../lib/grammar";
+import { Host } from "../lib/host";
 import { EmitFormat } from "../lib/options";
 import { getGrammarFiles } from "./resources";
 import { writeTokens, writeDiagnostics, writeOutput, compareBaseline } from "./diff";
+import { CancellationTokenSource } from "prex";
+import { assert } from "chai";
 
 describe("Emitter", () => {
     defineTests();
 
+    it("cancelable", () => {
+        const cts = new CancellationTokenSource();
+        const grammar = new Grammar(["cancelable.grammar"], {}, Host.getHost({
+            readFile(file) { return ""; },
+            writeFile(file, content) { }
+        }), /*oldGrammar*/ undefined, cts.token);
+        grammar.check(/*sourceFile*/ undefined);
+        cts.cancel();
+        assert.throws(() => grammar.emit(/*sourceFile*/ undefined));
+    });
+
     function defineTests() {
         for (const file of getGrammarFiles()) {
             defineTest(basename(file), file, ".md", EmitFormat.markdown);

diff --git a/src/tests/parser-tests.ts b/src/tests/parser-tests.ts
@@ -6,10 +6,19 @@ import { SourceFile } from "../lib/nodes";
 import { Parser } from "../lib/parser";
 import { getGrammarFiles } from "./resources";
 import { writeNodes, writeDiagnostics, compareBaseline } from "./diff";
+import { CancellationTokenSource } from "prex";
+import { assert } from "chai";
 
 describe("Parser", () => {
     defineTests();
 
+    it("cancelable", () => {
+        const cts = new CancellationTokenSource();
+        const parser = new Parser(new DiagnosticMessages(), cts.token);
+        cts.cancel();
+        assert.throws(() => parser.parseSourceFile("cancelable.grammar", ""));
+    });
+
     function defineTests() {
         for (let file of getGrammarFiles()) {
             defineTest(basename(file), file);

diff --git a/src/tests/scanner-tests.ts b/src/tests/scanner-tests.ts
@@ -6,10 +6,22 @@ import { SourceFile } from "../lib/nodes";
 import { Scanner } from "../lib/scanner";
 import { getGrammarFiles } from "./resources";
 import { writeTokens, writeDiagnostics, compareBaseline } from "./diff";
+import { CancellationTokenSource } from "prex";
+import { assert } from "chai";
 
 describe("Scanner", () => {
     defineTests();
 
+    it("cancelable", () => {
+        const sourceFile = new SourceFile("cancelable.grammar", "");
+        const diagnostics = new DiagnosticMessages();
+        diagnostics.setSourceFile(sourceFile);
+        const cts = new CancellationTokenSource();
+        const scanner = new Scanner(sourceFile.filename, sourceFile.text, diagnostics, cts.token);
+        cts.cancel();
+        assert.throws(() => scanner.scan());
+    });
+
     function defineTests() {
         for (let file of getGrammarFiles()) {
             defineTest(basename(file), file);