Pick correct compilerOptions when checking if we can share emitSignat…

…ures (#50910)

* Pick correct compilerOptions when checking if we can share emitSignatures
Fixes #50902

* Add a note

* Rewording

src/compiler/builder.ts

@@ -173,10 +173,16 @@ namespace ts {
         const oldCompilerOptions = useOldState ? oldState!.compilerOptions : undefined;
         const canCopySemanticDiagnostics = useOldState && oldState!.semanticDiagnosticsPerFile && !!state.semanticDiagnosticsPerFile &&
             !compilerOptionsAffectSemanticDiagnostics(compilerOptions, oldCompilerOptions!);
+        // We can only reuse emit signatures (i.e. .d.ts signatures) if the .d.ts file is unchanged,
+        // which will eg be depedent on change in options like declarationDir and outDir options are unchanged.
+        // We need to look in oldState.compilerOptions, rather than oldCompilerOptions (i.e.we need to disregard useOldState) because
+        // oldCompilerOptions can be undefined if there was change in say module from None to some other option
+        // which would make useOldState as false since we can now use reference maps that are needed to track what to emit, what to check etc
+        // but that option change does not affect d.ts file name so emitSignatures should still be reused.
         const canCopyEmitSignatures = compilerOptions.composite &&
             oldState?.emitSignatures &&
             !outFilePath &&
-            !compilerOptionsAffectDeclarationPath(compilerOptions, oldCompilerOptions!);
+            !compilerOptionsAffectDeclarationPath(compilerOptions, oldState.compilerOptions);
         if (useOldState) {
             // Copy old state's changed files set
             oldState!.changedFilesSet?.forEach(value => state.changedFilesSet.add(value));

src/testRunner/unittests/tsc/composite.ts

@@ -81,5 +81,26 @@ namespace ts {
             }),
             commandLineArgs: ["--composite", "false", "--p", "src/project", "--tsBuildInfoFile", "null"],
         });
+
+        verifyTscWithEdits({
+            scenario: "composite",
+            subScenario: "converting to modules",
+            fs: () => loadProjectFromFiles({
+                "/src/project/src/main.ts": "const x = 10;",
+                "/src/project/tsconfig.json": JSON.stringify({
+                    compilerOptions: {
+                        module: "none",
+                        composite: true,
+                    },
+                }),
+            }),
+            commandLineArgs: ["-p", "/src/project"],
+            edits: [
+                {
+                    subScenario: "convert to modules",
+                    modifyFs: fs => replaceText(fs, "/src/project/tsconfig.json", "none", "es2015"),
+                }
+            ]
+        });
     });
 }

tests/baselines/reference/tsc/composite/converting-to-modules.js

@@ -0,0 +1,126 @@
+Input::
+//// [/lib/lib.d.ts]
+/// <reference no-default-lib="true"/>
+interface Boolean {}
+interface Function {}
+interface CallableFunction {}
+interface NewableFunction {}
+interface IArguments {}
+interface Number { toExponential: any; }
+interface Object {}
+interface RegExp {}
+interface String { charAt: any; }
+interface Array<T> { length: number; [n: number]: T; }
+interface ReadonlyArray<T> {}
+declare const console: { log(msg: any): void; };
+
+//// [/src/project/src/main.ts]
+const x = 10;
+
+//// [/src/project/tsconfig.json]
+{"compilerOptions":{"module":"none","composite":true}}
+
+
+
+Output::
+/lib/tsc -p /src/project
+exitCode:: ExitStatus.Success
+
+
+//// [/src/project/src/main.d.ts]
+declare const x = 10;
+
+
+//// [/src/project/src/main.js]
+var x = 10;
+
+
+//// [/src/project/tsconfig.tsbuildinfo]
+{"program":{"fileNames":["../../lib/lib.d.ts","./src/main.ts"],"fileInfos":[{"version":"3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };","affectsGlobalScope":true},{"version":"5029505981-const x = 10;","signature":"-3198459068-declare const x = 10;\r\n","affectsGlobalScope":true}],"options":{"composite":true,"module":0},"semanticDiagnosticsPerFile":[1,2],"latestChangedDtsFile":"./src/main.d.ts"},"version":"FakeTSVersion"}
+
+//// [/src/project/tsconfig.tsbuildinfo.readable.baseline.txt]
+{
+  "program": {
+    "fileNames": [
+      "../../lib/lib.d.ts",
+      "./src/main.ts"
+    ],
+    "fileInfos": {
+      "../../lib/lib.d.ts": {
+        "version": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "signature": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "affectsGlobalScope": true
+      },
+      "./src/main.ts": {
+        "version": "5029505981-const x = 10;",
+        "signature": "-3198459068-declare const x = 10;\r\n",
+        "affectsGlobalScope": true
+      }
+    },
+    "options": {
+      "composite": true,
+      "module": 0
+    },
+    "semanticDiagnosticsPerFile": [
+      "../../lib/lib.d.ts",
+      "./src/main.ts"
+    ],
+    "latestChangedDtsFile": "./src/main.d.ts"
+  },
+  "version": "FakeTSVersion",
+  "size": 816
+}
+
+
+
+Change:: convert to modules
+Input::
+//// [/src/project/tsconfig.json]
+{"compilerOptions":{"module":"es2015","composite":true}}
+
+
+
+Output::
+/lib/tsc -p /src/project
+exitCode:: ExitStatus.Success
+
+
+//// [/src/project/src/main.js] file written with same contents
+//// [/src/project/tsconfig.tsbuildinfo]
+{"program":{"fileNames":["../../lib/lib.d.ts","./src/main.ts"],"fileInfos":[{"version":"3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };","affectsGlobalScope":true},{"version":"5029505981-const x = 10;","signature":"-3198459068-declare const x = 10;\r\n","affectsGlobalScope":true}],"options":{"composite":true,"module":5},"referencedMap":[],"exportedModulesMap":[],"semanticDiagnosticsPerFile":[1,2],"latestChangedDtsFile":"./src/main.d.ts"},"version":"FakeTSVersion"}
+
+//// [/src/project/tsconfig.tsbuildinfo.readable.baseline.txt]
+{
+  "program": {
+    "fileNames": [
+      "../../lib/lib.d.ts",
+      "./src/main.ts"
+    ],
+    "fileInfos": {
+      "../../lib/lib.d.ts": {
+        "version": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "signature": "3858781397-/// <reference no-default-lib=\"true\"/>\ninterface Boolean {}\ninterface Function {}\ninterface CallableFunction {}\ninterface NewableFunction {}\ninterface IArguments {}\ninterface Number { toExponential: any; }\ninterface Object {}\ninterface RegExp {}\ninterface String { charAt: any; }\ninterface Array<T> { length: number; [n: number]: T; }\ninterface ReadonlyArray<T> {}\ndeclare const console: { log(msg: any): void; };",
+        "affectsGlobalScope": true
+      },
+      "./src/main.ts": {
+        "version": "5029505981-const x = 10;",
+        "signature": "-3198459068-declare const x = 10;\r\n",
+        "affectsGlobalScope": true
+      }
+    },
+    "options": {
+      "composite": true,
+      "module": 5
+    },
+    "referencedMap": {},
+    "exportedModulesMap": {},
+    "semanticDiagnosticsPerFile": [
+      "../../lib/lib.d.ts",
+      "./src/main.ts"
+    ],
+    "latestChangedDtsFile": "./src/main.d.ts"
+  },
+  "version": "FakeTSVersion",
+  "size": 859
+}
+