Navigate to test source file when clicking CTest in Test Explorer (#4761)

* Initial plan

* feat: navigate to test source file when clicking test in Test Explorer

Match test executables to CMake target source files via the code model,
so clicking a CTest unit test in the Test Explorer navigates to the
actual test source file instead of CMakeLists.txt.

Priority order for test location resolution:
1. DEF_SOURCE_LINE property (user-specified)
2. Code model source file matching (new - matches executable to target)
3. Backtrace fallback (CMakeLists.txt location)

Fixes #4449

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

* Remove PR citation from changelog entry

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

* Fix null safety: guard test.command access in refreshTestsInTestExplorer

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

---------

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

Author: Copilot

CHANGELOG.md

@@ -14,6 +14,7 @@ Features:
 - Support `targetName` argument for launch-target command substitutions (`cmake.launchTargetPath`, etc.) via `${input:...}` variables, enabling build-before-run for non-active executable targets without changing the active launch target. [#4656](https://github.com/microsoft/vscode-cmake-tools/issues/4656)
 
 Improvements:
+- Clicking on a CTest unit test in the Test Explorer now navigates to the test source file by matching the test executable to its CMake target's source files. [#4449](https://github.com/microsoft/vscode-cmake-tools/issues/4449)
 - Make "CMake: Add ... Preset" commands available in the command palette when `cmake.useCMakePresets` is set to `auto`, even before a CMakePresets.json file exists. [#4401](https://github.com/microsoft/vscode-cmake-tools/issues/4401)
 - Improve CMake syntax highlighting with command-scoped keyword rules, expanded variable recognition, and better generator-expression support. Remove obsolete deprecated-keyword entries that caused false positives on user-defined names. [#4709](https://github.com/microsoft/vscode-cmake-tools/issues/4709) [#4508](https://github.com/microsoft/vscode-cmake-tools/issues/4508) [#4613](https://github.com/microsoft/vscode-cmake-tools/issues/4613)
 - Add MSVC linker error problem matching to the Problems pane. [#4675](https://github.com/microsoft/vscode-cmake-tools/pull/4675) [@bradphelan](https://github.com/bradphelan)

src/ctest.ts

@@ -778,6 +778,40 @@ export class CTestDriver implements vscode.Disposable {
         return undefined;
     }
 
+    /**
+     * Builds a map from normalized executable paths to source file information
+     * by looking at the code model content from the CMake driver.
+     */
+    private buildExecutableToSourcesMap(driver: CMakeDriver): Map<string, { sourceDir: string; sources: string[] }> {
+        const map = new Map<string, { sourceDir: string; sources: string[] }>();
+        const codeModelContent = driver.codeModelContent;
+        if (!codeModelContent) {
+            return map;
+        }
+        for (const config of codeModelContent.configurations) {
+            for (const project of config.projects) {
+                for (const target of project.targets) {
+                    if (target.artifacts && target.fileGroups && target.sourceDirectory) {
+                        // Collect compilable (non-generated) source files from file groups
+                        const sources: string[] = [];
+                        for (const fg of target.fileGroups) {
+                            if (fg.language && !fg.isGenerated && fg.sources) {
+                                sources.push(...fg.sources);
+                            }
+                        }
+                        if (sources.length > 0) {
+                            for (const artifact of target.artifacts) {
+                                const normalizedArtifact = util.platformNormalizePath(artifact);
+                                map.set(normalizedArtifact, { sourceDir: target.sourceDirectory, sources });
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        return map;
+    }
+
     private createTestItemAndSuiteTree(testName: string, testExplorerRoot: vscode.TestItem, initializedTestExplorer: vscode.TestController, uri?: vscode.Uri): TestAndParentSuite {
         let parentSuiteItem = testExplorerRoot;
         let testLabel = testName;
@@ -848,6 +882,9 @@ export class CTestDriver implements vscode.Disposable {
             }
         } else if (testType === "CTestInfo" && this.tests !== undefined) {
             if (this.tests && this.tests.kind === 'ctestInfo') {
+                // Build a map from executable paths to source files using the code model
+                const executableToSources = this.buildExecutableToSourcesMap(driver);
+
                 this.tests.tests.forEach(test => {
                     let testDefFile: string | undefined;
                     let testDefLine: number | undefined;
@@ -868,6 +905,16 @@ export class CTestDriver implements vscode.Disposable {
                         }
                     }
 
+                    // Try to find the test source file by matching the test executable to a CMake target
+                    if (!testDefFile && test.command && test.command.length > 0) {
+                        const testExe = util.platformNormalizePath(test.command[0]);
+                        const targetInfo = executableToSources.get(testExe);
+                        if (targetInfo && targetInfo.sources.length > 0) {
+                            testDefFile = path.resolve(targetInfo.sourceDir, targetInfo.sources[0]);
+                            testDefLine = 1;
+                        }
+                    }
+
                     const nodes = this.tests!.backtraceGraph.nodes;
                     if (!testDefFile && test.backtrace !== undefined && nodes[test.backtrace] !== undefined) {
                         // Use the backtrace graph to find the file and line number