feat(compiler-cli): add support for using TypeScript 4.1 (#39571)

This change enables projects to be built with TypeScript 4.1. Support for TypeScript 4.0 is also retained. PR Close #39571
angular · Nov 25, 2020 · a7e7c21 · a7e7c21
1 parent 2786292
commit a7e7c21
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Showing 2 changed files with 5 additions and 2 deletions.
diff --git a/packages/compiler-cli/src/transformers/program.ts b/packages/compiler-cli/src/transformers/program.ts
@@ -654,7 +654,10 @@ class AngularCompilerProgram implements Program {
     // - we cache all the files in the hostAdapter
     // - new new stubs use the exactly same imports/exports as the old once (we assert that in
     // hostAdapter.updateGeneratedFile).
-    if (tsStructureIsReused(tmpProgram) !== StructureIsReused.Completely) {
+    // TS 4.1+ stores the reuse state in the new program
+    const checkReuseProgram =
+        (ts.versionMajorMinor as string) === '4.0' ? tmpProgram : this._tsProgram;
+    if (tsStructureIsReused(checkReuseProgram) !== StructureIsReused.Completely) {
       throw new Error(`Internal Error: The structure of the program changed during codegen.`);
     }
   }

diff --git a/packages/compiler-cli/src/typescript_support.ts b/packages/compiler-cli/src/typescript_support.ts
@@ -25,7 +25,7 @@ const MIN_TS_VERSION = '4.0.0';
  * Note: this check is disabled in g3, search for
  * `angularCompilerOptions.disableTypeScriptVersionCheck` config param value in g3.
  */
-const MAX_TS_VERSION = '4.1.0';
+const MAX_TS_VERSION = '4.2.0';
 
 /**
  * The currently used version of TypeScript, which can be adjusted for testing purposes using