Clear Problems pane on build start and populate diagnostics incrementally (#4711)

* Initial plan

* feat: clear Problems tab on build start and populate diagnostics incrementally (#4608)

Co-authored-by: snehara99 <[email protected]>

* Address code review feedback: simplify enableOutputParsers check and add comment

Co-authored-by: snehara99 <[email protected]>

* Simplify to minimal change: only clear build diagnostics at build start

Co-authored-by: snehara99 <[email protected]>

* Add back incremental build diagnostics without source tracking

Co-authored-by: snehara99 <[email protected]>

* Add source tracking to incremental diagnostics for enableOutputParsers filtering and source labels

Co-authored-by: snehara99 <[email protected]>

* Derive source names dynamically from Compilers properties instead of hardcoded list

Co-authored-by: snehara99 <[email protected]>

* merge fixes

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: snehara99 <[email protected]>
Co-authored-by: Sneha Ramachandran <[email protected]>

Author: Copilot

CHANGELOG.md

@@ -5,6 +5,7 @@
 Features:
 - triple: Add riscv32be riscv64be support. [#4648](https://github.com/microsoft/vscode-cmake-tools/pull/4648) [@lygstate](https://github.com/lygstate)
 - Add command to clear build diagnostics from the Problems pane. [#4691](https://github.com/microsoft/vscode-cmake-tools/pull/4691)
+- Clear build diagnostics from the Problems pane when a new build starts and populate them incrementally during the build. [#4608](https://github.com/microsoft/vscode-cmake-tools/issues/4608)
 - Add individual CTest test nodes to the Project Outline with inline run/debug buttons, and enable debugging tests from both the Outline and Test Explorer without requiring a launch.json. [#4721](https://github.com/microsoft/vscode-cmake-tools/pull/4721)
 - Add "Delete Cache, Reconfigure and Build" command that chains cache deletion, reconfiguration, and build into a single action. [#4723](https://github.com/microsoft/vscode-cmake-tools/pull/4723)
 - Add "Set Build and Launch/Debug Target" command that sets both the build target and launch target simultaneously. [#4732](https://github.com/microsoft/vscode-cmake-tools/pull/4732)

src/cmakeProject.ts

@@ -28,7 +28,7 @@ import { CPackDriver } from '@cmt/cpack';
 import { WorkflowDriver } from '@cmt/workflow';
 import { CMakeBuildConsumer } from '@cmt/diagnostics/build';
 import { CMakeOutputConsumer } from '@cmt/diagnostics/cmake';
-import { FileDiagnostic, populateCollection } from '@cmt/diagnostics/util';
+import { FileDiagnostic, addDiagnosticToCollection, diagnosticSeverity, populateCollection } from '@cmt/diagnostics/util';
 import { expandStrings, expandString, ExpansionOptions } from '@cmt/expand';
 import { CMakeGenerator, Kit, SpecialKits } from '@cmt/kits/kit';
 import * as logging from '@cmt/logging';
@@ -2106,6 +2106,9 @@ export class CMakeProject {
         try {
             this.statusMessage.set(localize('building.status', 'Building'));
             this.isBusy.set(true);
+            if (drv.config.parseBuildDiagnostics) {
+                collections.build.clear();
+            }
             let rc: number | null;
             if (taskConsumer) {
                 buildLogger.info(localize('starting.build', 'Starting build'));
@@ -2125,6 +2128,24 @@ export class CMakeProject {
                 };
             } else {
                 consumer = new CMakeBuildConsumer(buildLogger, drv.config);
+                if (drv.config.parseBuildDiagnostics) {
+                    consumer.onDiagnostic(({ source, diagnostic: rawDiag }) => {
+                        if (!drv!.config.enableOutputParsers?.includes(source.toLowerCase())) {
+                            return;
+                        }
+                        const severity = diagnosticSeverity(rawDiag.severity);
+                        if (severity === undefined) {
+                            return;
+                        }
+                        const filepath = util.resolvePath(rawDiag.file, drv!.binaryDir);
+                        const diag = new vscode.Diagnostic(rawDiag.location, rawDiag.message, severity);
+                        diag.source = source;
+                        if (rawDiag.code) {
+                            diag.code = rawDiag.code;
+                        }
+                        addDiagnosticToCollection(collections.build, { filepath, diag });
+                    });
+                }
                 return await vscode.window.withProgress(
                     {
                         location: vscode.ProgressLocation.Window,

src/diagnostics/build.ts

@@ -15,8 +15,8 @@ import * as gnu_ld from '@cmt/diagnostics/gnu-ld';
 import * as mvsc from '@cmt/diagnostics/msvc';
 import * as iar from '@cmt/diagnostics/iar';
 import * as iwyu from '@cmt/diagnostics/iwyu';
+import { FileDiagnostic, RawDiagnostic, RawDiagnosticParser, diagnosticSeverity } from '@cmt/diagnostics/util';
 import { CustomParser } from '@cmt/diagnostics/custom';
-import { FileDiagnostic, RawDiagnostic, RawDiagnosticParser } from '@cmt/diagnostics/util';
 import { ConfigurationReader } from '@cmt/config';
 import { fs } from '@cmt/pr';
 
@@ -32,6 +32,12 @@ export class Compilers {
     iwyu = new iwyu.Parser();
 }
 
+export interface RawDiagnosticWithSource {
+    /** The parser that produced this diagnostic (e.g. 'GCC', 'MSVC'). Matches the keys used in `enableOutputParsers`. */
+    source: string;
+    diagnostic: RawDiagnostic;
+}
+
 export class CompileOutputConsumer implements OutputConsumer {
     readonly customParsers: Map<string, CustomParser> = new Map();
 
@@ -45,6 +51,21 @@ export class CompileOutputConsumer implements OutputConsumer {
 
     compilers = new Compilers();
 
+    private readonly _onDiagnosticEmitter = new vscode.EventEmitter<RawDiagnosticWithSource>();
+
+    /**
+     * Event fired when a new diagnostic is parsed from compiler output.
+     * Includes the source parser name so subscribers can filter by `enableOutputParsers`
+     * and set `diag.source` for display in the Problems pane.
+     */
+    get onDiagnostic() {
+        return this._onDiagnosticEmitter.event;
+    }
+
+    dispose() {
+        this._onDiagnosticEmitter.dispose();
+    }
+
     // Defer all output to the `error` method
     output(line: string) {
         this.error(line);
@@ -53,13 +74,28 @@ export class CompileOutputConsumer implements OutputConsumer {
     error(line: string) {
         // Built-in parsers get first priority
         for (const cand in this.compilers) {
-            if (this.compilers[cand].handleLine(line)) {
+            const parser = this.compilers[cand];
+            const countBefore = parser.diagnostics.length;
+            if (parser.handleLine(line)) {
+                if (parser.diagnostics.length > countBefore) {
+                    this._onDiagnosticEmitter.fire({
+                        source: cand.toUpperCase(),
+                        diagnostic: parser.diagnostics[parser.diagnostics.length - 1]
+                    });
+                }
                 return;
             }
         }
         // Custom user-defined parsers run after built-ins
-        for (const [, parser] of this.customParsers) {
+        for (const [name, parser] of this.customParsers) {
+            const countBefore = parser.diagnostics.length;
             if (parser.handleLine(line)) {
+                if (parser.diagnostics.length > countBefore) {
+                    this._onDiagnosticEmitter.fire({
+                        source: name,
+                        diagnostic: parser.diagnostics[parser.diagnostics.length - 1]
+                    });
+                }
                 return;
             }
         }
@@ -79,33 +115,10 @@ export class CompileOutputConsumer implements OutputConsumer {
         const diags_by_file = new Map<string, vscode.Diagnostic[]>();
         const linkerHandler = this.createLinkerDiagnosticsHandler(basePaths);
 
-        const severity_of = (p: string) => {
-            switch (p) {
-                case 'warning':
-                    return vscode.DiagnosticSeverity.Warning;
-                case 'catastrophic error':
-                case 'fatal error':
-                case 'error':
-                    return vscode.DiagnosticSeverity.Error;
-                case 'note':
-                case 'info':
-                case 'remark':
-                    return vscode.DiagnosticSeverity.Information;
-            }
-            // tslint:disable-next-line
-            console.warn('Unknown diagnostic severity level: ' + p);
-            return undefined;
-        };
-
-        const by_source = {
-            GCC: this.compilers.gcc.diagnostics,
-            MSVC: this.compilers.msvc.diagnostics,
-            GHS: this.compilers.ghs.diagnostics,
-            DIAB: this.compilers.diab.diagnostics,
-            GNULD: this.compilers.gnuld.diagnostics,
-            IAR: this.compilers.iar.diagnostics,
-            IWYU: this.compilers.iwyu.diagnostics
-        };
+        const by_source: Record<string, readonly RawDiagnostic[]> = {};
+        for (const name in this.compilers) {
+            by_source[name.toUpperCase()] = this.compilers[name].diagnostics;
+        }
         const parsers = util.objectPairs(by_source)
             .filter(([source, _]) => this.config.enableOutputParsers?.includes(source.toLowerCase()) ?? false);
         const arrs: FileDiagnostic[] = [];
@@ -115,7 +128,7 @@ export class CompileOutputConsumer implements OutputConsumer {
             for (const raw_diag of diags) {
                 await linkerHandler.collect(raw_diag, source, arrs.length);
                 const filepath = await this.resolvePath(raw_diag.file, basePaths);
-                const severity = severity_of(raw_diag.severity);
+                const severity = diagnosticSeverity(raw_diag.severity);
                 if (severity === undefined) {
                     continue;
                 }
@@ -148,7 +161,7 @@ export class CompileOutputConsumer implements OutputConsumer {
         for (const [name, parser] of this.customParsers) {
             for (const raw_diag of parser.diagnostics) {
                 const filepath = await this.resolvePath(raw_diag.file, basePaths);
-                const severity = severity_of(raw_diag.severity);
+                const severity = diagnosticSeverity(raw_diag.severity);
                 if (severity === undefined) {
                     continue;
                 }
@@ -323,8 +336,16 @@ export class CMakeBuildConsumer extends proc.CommandConsumer implements vscode.D
 
     readonly compileConsumer: CompileOutputConsumer;
 
+    /**
+     * Event fired when a new diagnostic is parsed from compiler output
+     */
+    get onDiagnostic() {
+        return this.compileConsumer.onDiagnostic;
+    }
+
     dispose() {
         this._onProgressEmitter.dispose();
+        this.compileConsumer.dispose();
     }
 
     error(line: string) {

src/diagnostics/util.ts

@@ -58,6 +58,27 @@ export function oneLess(num: number | string): number {
     }
 }
 
+/**
+ * Convert a severity string from compiler output to a `vscode.DiagnosticSeverity`.
+ * @param severity The severity string (e.g. 'warning', 'error', 'note')
+ * @returns The corresponding `vscode.DiagnosticSeverity`, or `undefined` if unknown
+ */
+export function diagnosticSeverity(severity: string): vscode.DiagnosticSeverity | undefined {
+    switch (severity) {
+        case 'warning':
+            return vscode.DiagnosticSeverity.Warning;
+        case 'catastrophic error':
+        case 'fatal error':
+        case 'error':
+            return vscode.DiagnosticSeverity.Error;
+        case 'note':
+        case 'info':
+        case 'remark':
+            return vscode.DiagnosticSeverity.Information;
+    }
+    return undefined;
+}
+
 /**
  * Inserts a list of `FileDiagnostic` instances into a diagnostic collection.
  * @param coll The `vscode.DiagnosticCollecion` to populate.
@@ -82,6 +103,18 @@ export function populateCollection(coll: vscode.DiagnosticCollection, fdiags: It
     });
 }
 
+/**
+ * Adds a single `FileDiagnostic` to a diagnostic collection without clearing existing entries.
+ * @param coll The `vscode.DiagnosticCollection` to add to.
+ * @param fdiag The `FileDiagnostic` to add.
+ */
+export function addDiagnosticToCollection(coll: vscode.DiagnosticCollection, fdiag: FileDiagnostic) {
+    const uri = vscode.Uri.file(fdiag.filepath);
+    const existing = coll.get(uri);
+    const diags = existing ? [...existing, fdiag.diag] : [fdiag.diag];
+    coll.set(uri, diags);
+}
+
 /**
  * Base class for parsing raw diagnostic information on a line-by-line basis
  */

test/unit-tests/diagnostics.test.ts

@@ -14,7 +14,7 @@ import { ExtensionConfigurationSettings, ConfigurationReader } from '../../src/c
 import { CustomParser, BuildProblemMatcherConfig } from '@cmt/diagnostics/custom';
 import { platformPathEquivalent, resolvePath } from '@cmt/util';
 import { CMakeOutputConsumer } from '@cmt/diagnostics/cmake';
-import { populateCollection } from '@cmt/diagnostics/util';
+import { populateCollection, addDiagnosticToCollection, diagnosticSeverity } from '@cmt/diagnostics/util';
 import collections from '@cmt/diagnostics/collections';
 import { getTestResourceFilePath } from '@test/util';
 import { Logger } from '@cmt/logging';
@@ -1295,6 +1295,69 @@ suite('Diagnostics', () => {
         expect(collections.presets.has(testUri)).to.be.false;
     });
 
+    test('diagnosticSeverity returns correct severities', () => {
+        expect(diagnosticSeverity('warning')).to.eq(vscode.DiagnosticSeverity.Warning);
+        expect(diagnosticSeverity('error')).to.eq(vscode.DiagnosticSeverity.Error);
+        expect(diagnosticSeverity('fatal error')).to.eq(vscode.DiagnosticSeverity.Error);
+        expect(diagnosticSeverity('catastrophic error')).to.eq(vscode.DiagnosticSeverity.Error);
+        expect(diagnosticSeverity('note')).to.eq(vscode.DiagnosticSeverity.Information);
+        expect(diagnosticSeverity('info')).to.eq(vscode.DiagnosticSeverity.Information);
+        expect(diagnosticSeverity('remark')).to.eq(vscode.DiagnosticSeverity.Information);
+        expect(diagnosticSeverity('unknown')).to.be.undefined;
+    });
+
+    test('addDiagnosticToCollection adds to empty collection', () => {
+        const coll = vscode.languages.createDiagnosticCollection('test-add-diag');
+        const diag = new vscode.Diagnostic(new vscode.Range(0, 0, 0, 10), 'test error', vscode.DiagnosticSeverity.Error);
+        addDiagnosticToCollection(coll, { filepath: '/test/file.cpp', diag });
+        const uri = vscode.Uri.file('/test/file.cpp');
+        expect(coll.has(uri)).to.be.true;
+        expect(coll.get(uri)!.length).to.eq(1);
+        coll.dispose();
+    });
+
+    test('addDiagnosticToCollection appends to existing diagnostics', () => {
+        const coll = vscode.languages.createDiagnosticCollection('test-add-diag-append');
+        const diag1 = new vscode.Diagnostic(new vscode.Range(0, 0, 0, 10), 'error 1', vscode.DiagnosticSeverity.Error);
+        const diag2 = new vscode.Diagnostic(new vscode.Range(1, 0, 1, 10), 'error 2', vscode.DiagnosticSeverity.Error);
+        addDiagnosticToCollection(coll, { filepath: '/test/file.cpp', diag: diag1 });
+        addDiagnosticToCollection(coll, { filepath: '/test/file.cpp', diag: diag2 });
+        const uri = vscode.Uri.file('/test/file.cpp');
+        expect(coll.has(uri)).to.be.true;
+        expect(coll.get(uri)!.length).to.eq(2);
+        coll.dispose();
+    });
+
+    test('CompileOutputConsumer fires onDiagnostic event with source', () => {
+        const consumer = new diags.CompileOutputConsumer(new ConfigurationReader({} as ExtensionConfigurationSettings));
+        const fired: diags.RawDiagnosticWithSource[] = [];
+        consumer.onDiagnostic(e => fired.push(e));
+        feedLines(consumer, [], [
+            '/some/path/here:4:26: error: some error message'
+        ]);
+        expect(fired).to.have.length(1);
+        expect(fired[0].source).to.eq('GCC');
+        expect(fired[0].diagnostic.severity).to.eq('error');
+        expect(fired[0].diagnostic.message).to.eq('some error message');
+        consumer.dispose();
+    });
+
+    test('CompileOutputConsumer fires onDiagnostic for each diagnostic with source', () => {
+        const consumer = new diags.CompileOutputConsumer(new ConfigurationReader({} as ExtensionConfigurationSettings));
+        const fired: diags.RawDiagnosticWithSource[] = [];
+        consumer.onDiagnostic(e => fired.push(e));
+        feedLines(consumer, [], [
+            '/path/a.cpp:1:1: warning: first warning',
+            '/path/b.cpp:2:1: error: first error'
+        ]);
+        expect(fired).to.have.length(2);
+        expect(fired[0].source).to.eq('GCC');
+        expect(fired[0].diagnostic.severity).to.eq('warning');
+        expect(fired[1].source).to.eq('GCC');
+        expect(fired[1].diagnostic.severity).to.eq('error');
+        consumer.dispose();
+    });
+
     test('CMakeOutputConsumer logs stdout lines at trace level, not info', () => {
         const spy = new SpyLogger();
         const consumerWithLogger = new CMakeOutputConsumer('dummyPath', spy);