testing: polish attributable coverage API, fix coverage reporting in selfhost (#215559)

.vscode/extensions/vscode-selfhost-test-provider/src/coverageProvider.ts

@@ -5,7 +5,7 @@
 
 import { IstanbulCoverageContext } from 'istanbul-to-vscode';
 import * as vscode from 'vscode';
-import { SourceLocationMapper, SourceMapStore } from './testOutputScanner';
+import { SearchStrategy, SourceLocationMapper, SourceMapStore } from './testOutputScanner';
 import { IScriptCoverage, OffsetToPosition, RangeCoverageTracker } from './v8CoverageWrangling';
 
 export const istanbulCoverageContext = new IstanbulCoverageContext();
@@ -18,7 +18,7 @@ export const istanbulCoverageContext = new IstanbulCoverageContext();
 export class PerTestCoverageTracker {
 	private readonly scripts = new Map</* script ID */ string, Script>();
 
-	constructor(private readonly maps: SourceMapStore) {}
+	constructor(private readonly maps: SourceMapStore) { }
 
 	public add(coverage: IScriptCoverage, test?: vscode.TestItem) {
 		const script = this.scripts.get(coverage.scriptId);
@@ -71,11 +71,7 @@ class Script {
 	public async report(run: vscode.TestRun) {
 		const mapper = await this.maps.getSourceLocationMapper(this.uri.toString());
 		const originalUri = (await this.maps.getSourceFile(this.uri.toString())) || this.uri;
-
-		run.addCoverage(this.overall.report(originalUri, this.converter, mapper));
-		for (const [test, projection] of this.perItem) {
-			run.addCoverage(projection.report(originalUri, this.converter, mapper, test));
-		}
+		run.addCoverage(this.overall.report(originalUri, this.converter, mapper, this.perItem));
 	}
 }
 
@@ -88,6 +84,43 @@ class ScriptCoverageTracker {
 		}
 	}
 
+	public *toDetails(
+		uri: vscode.Uri,
+		convert: OffsetToPosition,
+		mapper: SourceLocationMapper | undefined,
+	) {
+		for (const range of this.coverage) {
+			if (range.start === range.end) {
+				continue;
+			}
+
+			const startCov = convert.toLineColumn(range.start);
+			let start = new vscode.Position(startCov.line, startCov.column);
+
+			const endCov = convert.toLineColumn(range.end);
+			let end = new vscode.Position(endCov.line, endCov.column);
+			if (mapper) {
+				const startMap = mapper(start.line, start.character, SearchStrategy.FirstAfter);
+				const endMap = startMap && mapper(end.line, end.character, SearchStrategy.FirstBefore);
+				if (!endMap || uri.toString().toLowerCase() !== endMap.uri.toString().toLowerCase()) {
+					continue;
+				}
+				start = startMap.range.start;
+				end = endMap.range.end;
+			}
+
+			for (let i = start.line; i <= end.line; i++) {
+				yield new vscode.StatementCoverage(
+					range.covered,
+					new vscode.Range(
+						new vscode.Position(i, i === start.line ? start.character : 0),
+						new vscode.Position(i, i === end.line ? end.character : Number.MAX_SAFE_INTEGER)
+					)
+				);
+			}
+		}
+	}
+
 	/**
 	 * Generates the script's coverage for the test run.
 	 *
@@ -98,53 +131,27 @@ class ScriptCoverageTracker {
 		uri: vscode.Uri,
 		convert: OffsetToPosition,
 		mapper: SourceLocationMapper | undefined,
-		item?: vscode.TestItem
+		items: Map<vscode.TestItem, ScriptCoverageTracker>,
 	): V8CoverageFile {
-		const file = new V8CoverageFile(uri, item);
-
-		for (const range of this.coverage) {
-			if (range.start === range.end) {
-				continue;
-			}
-
-			const startCov = convert.toLineColumn(range.start);
-			let start = new vscode.Position(startCov.line, startCov.column);
-
-			const endCov = convert.toLineColumn(range.end);
-			let end = new vscode.Position(endCov.line, endCov.column);
-			if (mapper) {
-				const startMap = mapper(start.line, start.character);
-				const endMap = startMap && mapper(end.line, end.character);
-				if (!endMap || uri.toString().toLowerCase() !== endMap.uri.toString().toLowerCase()) {
-					continue;
-				}
-				start = startMap.range.start;
-				end = endMap.range.end;
-			}
-
-			for (let i = start.line; i <= end.line; i++) {
-				file.add(
-					new vscode.StatementCoverage(
-						range.covered,
-						new vscode.Range(
-							new vscode.Position(i, i === start.line ? start.character : 0),
-							new vscode.Position(i, i === end.line ? end.character : Number.MAX_SAFE_INTEGER)
-						)
-					)
-				);
-			}
+		const file = new V8CoverageFile(uri, items, convert, mapper);
+		for (const detail of this.toDetails(uri, convert, mapper)) {
+			file.add(detail);
 		}
 
 		return file;
 	}
 }
 
-export class V8CoverageFile extends vscode.FileCoverage {
+export class V8CoverageFile extends vscode.FileCoverage2 {
 	public details: vscode.StatementCoverage[] = [];
 
-	constructor(uri: vscode.Uri, item?: vscode.TestItem) {
-		super(uri, { covered: 0, total: 0 });
-		(this as vscode.FileCoverage2).testItem = item;
+	constructor(
+		uri: vscode.Uri,
+		private readonly perTest: Map<vscode.TestItem, ScriptCoverageTracker>,
+		private readonly convert: OffsetToPosition,
+		private readonly mapper: SourceLocationMapper | undefined,
+	) {
+		super(uri, { covered: 0, total: 0 }, undefined, undefined, [...perTest.keys()]);
 	}
 
 	public add(detail: vscode.StatementCoverage) {
@@ -154,4 +161,9 @@ export class V8CoverageFile extends vscode.FileCoverage {
 			this.statementCoverage.covered++;
 		}
 	}
+
+	public testDetails(test: vscode.TestItem): vscode.FileCoverageDetail[] {
+		const t = this.perTest.get(test);
+		return t ? [...t.toDetails(this.uri, this.convert, this.mapper)] : [];
+	}
 }

.vscode/extensions/vscode-selfhost-test-provider/src/extension.ts

@@ -196,9 +196,9 @@ export async function activate(context: vscode.ExtensionContext) {
 		true
 	);
 
-	coverage.loadDetailedCoverage = async (_run, coverage) => {
+	(coverage as vscode.TestRunProfile2).loadDetailedCoverage = async (_run, coverage, _token, test) => {
 		if (coverage instanceof V8CoverageFile) {
-			return coverage.details;
+			return test ? coverage.testDetails(test) : coverage.details;
 		}
 
 		return [];

.vscode/extensions/vscode-selfhost-test-provider/src/testOutputScanner.ts

@@ -424,36 +424,62 @@ const tryMakeMarkdown = (message: string) => {
 const inlineSourcemapRe = /^\/\/# sourceMappingURL=data:application\/json;base64,(.+)/m;
 const sourceMapBiases = [GREATEST_LOWER_BOUND, LEAST_UPPER_BOUND] as const;
 
-export type SourceLocationMapper = (line: number, col: number) => vscode.Location | undefined;
+export const enum SearchStrategy {
+	FirstBefore = -1,
+	FirstAfter = 1,
+}
+
+export type SourceLocationMapper = (line: number, col: number, strategy: SearchStrategy) => vscode.Location | undefined;
 
 export class SourceMapStore {
 	private readonly cache = new Map</* file uri */ string, Promise<TraceMap | undefined>>();
 
-	async getSourceLocationMapper(fileUri: string) {
+	async getSourceLocationMapper(fileUri: string): Promise<SourceLocationMapper> {
 		const sourceMap = await this.loadSourceMap(fileUri);
-		return (line: number, col: number) => {
+		return (line, col, strategy) => {
 			if (!sourceMap) {
 				return undefined;
 			}
 
-			let smLine = line + 1;
+			// 1. Look for the ideal position on this line if it exists
+			const idealPosition = originalPositionFor(sourceMap, { column: col, line: line + 1, bias: SearchStrategy.FirstAfter ? GREATEST_LOWER_BOUND : LEAST_UPPER_BOUND });
+			if (idealPosition.line !== null && idealPosition.column !== null && idealPosition.source !== null) {
+				return new vscode.Location(
+					this.completeSourceMapUrl(sourceMap, idealPosition.source),
+					new vscode.Position(idealPosition.line - 1, idealPosition.column)
+				);
+			}
 
-			// if the range is after the end of mappings, adjust it to the last mapped line
+			// Otherwise get the first/last valid mapping on another line.
 			const decoded = decodedMappings(sourceMap);
-			if (decoded.length <= line) {
-				smLine = decoded.length; // base 1, no -1 needed
-				col = Number.MAX_SAFE_INTEGER;
+			const enum MapField {
+				COLUMN = 0,
+				SOURCES_INDEX = 1,
+				SOURCE_LINE = 2,
+				SOURCE_COLUMN = 3,
 			}
 
-			for (const bias of sourceMapBiases) {
-				const position = originalPositionFor(sourceMap, { column: col, line: smLine, bias });
-				if (position.line !== null && position.column !== null && position.source !== null) {
-					return new vscode.Location(
-						this.completeSourceMapUrl(sourceMap, position.source),
-						new vscode.Position(position.line - 1, position.column)
-					);
+			do {
+				line += strategy;
+				const segments = decoded[line];
+				if (!segments?.length) {
+					continue;
 				}
-			}
+
+				const index = strategy === SearchStrategy.FirstBefore
+					? findLastIndex(segments, s => s.length !== 1)
+					: segments.findIndex(s => s.length !== 1);
+				const segment = segments[index];
+
+				if (!segment || segment.length === 1) {
+					continue;
+				}
+
+				return new vscode.Location(
+					this.completeSourceMapUrl(sourceMap, sourceMap.sources[segment[MapField.SOURCES_INDEX]]!),
+					new vscode.Position(segment[MapField.SOURCE_LINE] - 1, segment[MapField.SOURCE_COLUMN])
+				);
+			} while (strategy === SearchStrategy.FirstBefore ? line > 0 : line < decoded.length);
 
 			return undefined;
 		};
@@ -461,7 +487,31 @@ export class SourceMapStore {
 
 	/** Gets an original location from a base 0 line and column */
 	async getSourceLocation(fileUri: string, line: number, col = 0) {
-		return this.getSourceLocationMapper(fileUri).then(m => m(line, col));
+		const sourceMap = await this.loadSourceMap(fileUri);
+		if (!sourceMap) {
+			return undefined;
+		}
+
+		let smLine = line + 1;
+
+		// if the range is after the end of mappings, adjust it to the last mapped line
+		const decoded = decodedMappings(sourceMap);
+		if (decoded.length <= line) {
+			smLine = decoded.length; // base 1, no -1 needed
+			col = Number.MAX_SAFE_INTEGER;
+		}
+
+		for (const bias of sourceMapBiases) {
+			const position = originalPositionFor(sourceMap, { column: col, line: smLine, bias });
+			if (position.line !== null && position.column !== null && position.source !== null) {
+				return new vscode.Location(
+					this.completeSourceMapUrl(sourceMap, position.source),
+					new vscode.Position(position.line - 1, position.column)
+				);
+			}
+		}
+
+		return undefined;
 	}
 
 	async getSourceFile(compiledUri: string) {
@@ -602,3 +652,13 @@ async function deriveSourceLocation(store: SourceMapStore, parts: RegExpMatchArr
 	const [, fileUri, line, col] = parts;
 	return store.getSourceLocation(fileUri, Number(line) - 1, Number(col));
 }
+
+function findLastIndex<T>(arr: T[], predicate: (value: T) => boolean) {
+	for (let i = arr.length - 1; i >= 0; i--) {
+		if (predicate(arr[i])) {
+			return i;
+		}
+	}
+
+	return -1;
+}