Handle when default project for file is solution with file actually referenced by one of the project references

src/server/project.ts

@@ -2164,6 +2164,24 @@ namespace ts.server {
             this.externalProjectRefCount--;
         }
 
+        /* @internal */
+        isSolution() {
+            return this.getRootFilesMap().size === 0 &&
+                !this.canConfigFileJsonReportNoInputFiles;
+        }
+
+        /* @internal */
+        getDefaultChildProjectFromSolution(info: ScriptInfo) {
+            Debug.assert(this.isSolution());
+            return forEachResolvedProjectReferenceProject(
+                this,
+                child => projectContainsInfoDirectly(child, info) ?
+                    child :
+                    undefined,
+                ProjectReferenceProjectLoadKind.Find
+            );
+        }
+
         /** Returns true if the project is needed by any of the open script info/external project */
         /* @internal */
         hasOpenRef() {
@@ -2184,12 +2202,16 @@ namespace ts.server {
                 return !!configFileExistenceInfo.openFilesImpactedByConfigFile.size;
             }
 
+            const isSolution = this.isSolution();
+
             // If there is no pending update for this project,
             // We know exact set of open files that get impacted by this configured project as the files in the project
             // The project is referenced only if open files impacted by this project are present in this project
             return forEachEntry(
                 configFileExistenceInfo.openFilesImpactedByConfigFile,
-                (_value, infoPath) => this.containsScriptInfo(this.projectService.getScriptInfoForPath(infoPath as Path)!)
+                (_value, infoPath) => isSolution ?
+                    !!this.getDefaultChildProjectFromSolution(this.projectService.getScriptInfoForPath(infoPath as Path)!) :
+                    this.containsScriptInfo(this.projectService.getScriptInfoForPath(infoPath as Path)!)
             ) || false;
         }
 

src/server/session.ts

@@ -431,10 +431,16 @@ namespace ts.server {
         if (initialLocation) {
             const defaultDefinition = getDefinitionLocation(defaultProject, initialLocation!);
             if (defaultDefinition) {
+                const getGeneratedDefinition = memoize(() => defaultProject.isSourceOfProjectReferenceRedirect(defaultDefinition.fileName) ?
+                    defaultDefinition :
+                    defaultProject.getLanguageService().getSourceMapper().tryGetGeneratedPosition(defaultDefinition));
+                const getSourceDefinition = memoize(() => defaultProject.isSourceOfProjectReferenceRedirect(defaultDefinition.fileName) ?
+                    defaultDefinition :
+                    defaultProject.getLanguageService().getSourceMapper().tryGetSourcePosition(defaultDefinition));
                 projectService.loadAncestorProjectTree(seenProjects);
                 projectService.forEachEnabledProject(project => {
                     if (!addToSeen(seenProjects, project)) return;
-                    const definition = mapDefinitionInProject(defaultDefinition, defaultProject, project);
+                    const definition = mapDefinitionInProject(defaultDefinition, project, getGeneratedDefinition, getSourceDefinition);
                     if (definition) {
                         toDo = callbackProjectAndLocation<TLocation>({ project, location: definition as TLocation }, projectService, toDo, seenProjects, cb);
                     }
@@ -447,17 +453,21 @@ namespace ts.server {
         }
     }
 
-    function mapDefinitionInProject(definition: DocumentPosition | undefined, definingProject: Project, project: Project): DocumentPosition | undefined {
+    function mapDefinitionInProject(
+        definition: DocumentPosition,
+        project: Project,
+        getGeneratedDefinition: () => DocumentPosition | undefined,
+        getSourceDefinition: () => DocumentPosition | undefined
+    ): DocumentPosition | undefined {
         // If the definition is actually from the project, definition is correct as is
-        if (!definition ||
-            project.containsFile(toNormalizedPath(definition.fileName)) &&
+        if (project.containsFile(toNormalizedPath(definition.fileName)) &&
             !isLocationProjectReferenceRedirect(project, definition)) {
             return definition;
         }
-        const mappedDefinition = definingProject.isSourceOfProjectReferenceRedirect(definition.fileName) ?
-            definition :
-            definingProject.getLanguageService().getSourceMapper().tryGetGeneratedPosition(definition);
-        return mappedDefinition && project.containsFile(toNormalizedPath(mappedDefinition.fileName)) ? mappedDefinition : undefined;
+        const generatedDefinition = getGeneratedDefinition();
+        if (generatedDefinition && project.containsFile(toNormalizedPath(generatedDefinition.fileName))) return generatedDefinition;
+        const sourceDefinition = getSourceDefinition();
+        return sourceDefinition && project.containsFile(toNormalizedPath(sourceDefinition.fileName)) ? sourceDefinition : undefined;
     }
 
     function isLocationProjectReferenceRedirect(project: Project, location: DocumentPosition | undefined) {

src/testRunner/unittests/publicApi.ts

@@ -1,4 +1,4 @@
-describe("Public APIs", () => {
+describe("unittests:: Public APIs", () => {
     function verifyApi(fileName: string) {
         const builtFile = `built/local/${fileName}`;
         const api = `api/${fileName}`;
@@ -32,7 +32,7 @@ describe("Public APIs", () => {
     });
 });
 
-describe("Public APIs:: token to string", () => {
+describe("unittests:: Public APIs:: token to string", () => {
     function assertDefinedTokenToString(initial: ts.SyntaxKind, last: ts.SyntaxKind) {
         for (let t = initial; t <= last; t++) {
             assert.isDefined(ts.tokenToString(t), `Expected tokenToString defined for ${ts.Debug.formatSyntaxKind(t)}`);
@@ -47,13 +47,13 @@ describe("Public APIs:: token to string", () => {
     });
 });
 
-describe("Public APIs:: createPrivateIdentifier", () => {
+describe("unittests:: Public APIs:: createPrivateIdentifier", () => {
     it("throws when name doesn't start with #", () => {
         assert.throw(() => ts.createPrivateIdentifier("not"), "Debug Failure. First character of private identifier must be #: not");
     });
 });
 
-describe("Public APIs:: isPropertyName", () => {
+describe("unittests:: Public APIs:: isPropertyName", () => {
     it("checks if a PrivateIdentifier is a valid property name", () => {
         const prop = ts.createPrivateIdentifier("#foo");
         assert.isTrue(ts.isPropertyName(prop), "PrivateIdentifier must be a valid property name.");

src/testRunner/unittests/tsserver/helpers.ts

@@ -716,6 +716,69 @@ namespace ts.projectSystem {
             assert.isFalse(event.event.endsWith("Diag"), JSON.stringify(event));
         }
     }
+    export function projectLoadingStartEvent(projectName: string, reason: string, seq?: number): protocol.ProjectLoadingStartEvent {
+        return {
+            seq: seq || 0,
+            type: "event",
+            event: server.ProjectLoadingStartEvent,
+            body: { projectName, reason }
+        };
+    }
+
+    export function projectLoadingFinishEvent(projectName: string, seq?: number): protocol.ProjectLoadingFinishEvent {
+        return {
+            seq: seq || 0,
+            type: "event",
+            event: server.ProjectLoadingFinishEvent,
+            body: { projectName }
+        };
+    }
+
+    export function projectInfoTelemetryEvent(seq?: number): protocol.TelemetryEvent {
+        return telemetryEvent(server.ProjectInfoTelemetryEvent, "", seq);
+    }
+
+    function telemetryEvent(telemetryEventName: string, payload: any, seq?: number): protocol.TelemetryEvent {
+        return {
+            seq: seq || 0,
+            type: "event",
+            event: "telemetry",
+            body: {
+                telemetryEventName,
+                payload
+            }
+        };
+    }
+
+    export function configFileDiagEvent(triggerFile: string, configFile: string, diagnostics: protocol.DiagnosticWithFileName[], seq?: number): protocol.ConfigFileDiagnosticEvent {
+        return {
+            seq: seq || 0,
+            type: "event",
+            event: server.ConfigFileDiagEvent,
+            body: {
+                triggerFile,
+                configFile,
+                diagnostics
+            }
+        };
+    }
+
+    export function checkEvents(session: TestSession, expectedEvents: protocol.Event[]) {
+        const events = session.events;
+        assert.equal(events.length, expectedEvents.length, `Actual:: ${JSON.stringify(session.events, /*replacer*/ undefined, " ")}`);
+        expectedEvents.forEach((expectedEvent, index) => {
+            if (expectedEvent.event === "telemetry") {
+                // Ignore payload
+                const { body, ...actual } = events[index] as protocol.TelemetryEvent;
+                const { body: expectedBody, ...expected } = expectedEvent as protocol.TelemetryEvent;
+                assert.deepEqual(actual, expected, `Expected ${JSON.stringify(expectedEvent)} at ${index} in ${JSON.stringify(events)}`);
+                assert.equal(body.telemetryEventName, expectedBody.telemetryEventName, `Expected ${JSON.stringify(expectedEvent)} at ${index} in ${JSON.stringify(events)}`);
+            }
+            else {
+                checkNthEvent(session, expectedEvent, index, index === expectedEvents.length);
+            }
+        });
+    }
 
     export function checkNthEvent(session: TestSession, expectedEvent: protocol.Event, index: number, isMostRecent: boolean) {
         const events = session.events;