Fix diagnostic serialization crash

src/compiler/checker.ts

@@ -30116,7 +30116,7 @@ namespace ts {
                         const diags = max > 1 ? allDiagnostics[minIndex] : flatten(allDiagnostics);
                         Debug.assert(diags.length > 0, "No errors reported for 3 or fewer overload signatures");
                         const chain = chainDiagnosticMessages(
-                            map(diags, d => typeof d.messageText === "string" ? (d as DiagnosticMessageChain) : d.messageText),
+                            map(diags, createDiagnosticMessageChainFromDiagnostic),
                             Diagnostics.No_overload_matches_this_call);
                         // The below is a spread to guarantee we get a new (mutable) array - our `flatMap` helper tries to do "smart" optimizations where it reuses input
                         // arrays and the emptyArray singleton where possible, which is decidedly not what we want while we're still constructing this diagnostic

src/compiler/utilities.ts

@@ -1071,6 +1071,15 @@ namespace ts {
         };
     }
 
+    export function createDiagnosticMessageChainFromDiagnostic(diagnostic: DiagnosticRelatedInformation): DiagnosticMessageChain {
+        return typeof diagnostic.messageText === "string" ? {
+            code: diagnostic.code,
+            category: diagnostic.category,
+            messageText: diagnostic.messageText,
+            next: (diagnostic as DiagnosticMessageChain).next,
+        } : diagnostic.messageText;
+    }
+
     export function createDiagnosticForRange(sourceFile: SourceFile, range: TextRange, message: DiagnosticMessage): DiagnosticWithLocation {
         return {
             file: sourceFile,

src/testRunner/unittests/tsc/incremental.ts

@@ -418,5 +418,36 @@ declare global {
             incrementalScenarios: noChangeOnlyRuns,
             baselinePrograms: true
         });
+
+        verifyTscSerializedIncrementalEdits({
+            scenario: "incremental",
+            subScenario: "serializing error chains",
+            commandLineArgs: ["-p", `src/project`],
+            fs: () => loadProjectFromFiles({
+                "/src/project/tsconfig.json": JSON.stringify({
+                    compilerOptions: {
+                        incremental: true,
+                        strict: true,
+                        jsx: "react",
+                        module: "esnext",
+                    },
+                }),
+                "/src/project/index.tsx": Utils.dedent`
+                    declare namespace JSX {
+                        interface ElementChildrenAttribute { children: {}; }
+                        interface IntrinsicElements { div: {} }
+                    }
+
+                    declare var React: any;
+
+                    declare function Component(props: never): any;
+                    declare function Component(props: { children?: number }): any;
+                    (<Component>
+                        <div />
+                        <div />
+                    </Component>)`
+            }, `\ninterface ReadonlyArray<T> { readonly length: number }`),
+            incrementalScenarios: noChangeOnlyRuns,
+        });
     });
 }

tests/baselines/reference/tsc/incremental/initial-build/serializing-error-chains.js

@@ -0,0 +1,185 @@
+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; };
+interface ReadonlyArray<T> { readonly length: number }
+
+//// [/src/project/index.tsx]
+declare namespace JSX {
+    interface ElementChildrenAttribute { children: {}; }
+    interface IntrinsicElements { div: {} }
+}
+
+declare var React: any;
+
+declare function Component(props: never): any;
+declare function Component(props: { children?: number }): any;
+(<Component>
+    <div />
+    <div />
+</Component>)
+
+//// [/src/project/tsconfig.json]
+{"compilerOptions":{"incremental":true,"strict":true,"jsx":"react","module":"esnext"}}
+
+
+
+Output::
+/lib/tsc -p src/project
+src/project/index.tsx:10:3 - error TS2746: This JSX tag's 'children' prop expects a single child of type 'never', but multiple children were provided.
+
+10 (<Component>
+     ~~~~~~~~~
+
+src/project/index.tsx:10:3 - error TS2746: This JSX tag's 'children' prop expects a single child of type 'number | undefined', but multiple children were provided.
+
+10 (<Component>
+     ~~~~~~~~~
+
+src/project/index.tsx:10:3 - error TS2769: No overload matches this call.
+  This JSX tag's 'children' prop expects a single child of type 'never', but multiple children were provided.
+  This JSX tag's 'children' prop expects a single child of type 'number | undefined', but multiple children were provided.
+
+10 (<Component>
+     ~~~~~~~~~
+
+
+
+Found 3 errors in the same file, starting at: src/project/index.tsx:10
+
+exitCode:: ExitStatus.DiagnosticsPresent_OutputsGenerated
+
+
+//// [/src/project/index.js]
+"use strict";
+(React.createElement(Component, null,
+    React.createElement("div", null),
+    React.createElement("div", null)));
+
+
+//// [/src/project/tsconfig.tsbuildinfo]
+{"program":{"fileNames":["../../lib/lib.d.ts","./index.tsx"],"fileInfos":[{"version":"7198220534-/// <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; };\ninterface ReadonlyArray<T> { readonly length: number }","affectsGlobalScope":true},{"version":"42569361247-declare namespace JSX {\n    interface ElementChildrenAttribute { children: {}; }\n    interface IntrinsicElements { div: {} }\n}\n\ndeclare var React: any;\n\ndeclare function Component(props: never): any;\ndeclare function Component(props: { children?: number }): any;\n(<Component>\n    <div />\n    <div />\n</Component>)","affectsGlobalScope":true}],"options":{"jsx":2,"module":99,"strict":true},"referencedMap":[],"exportedModulesMap":[],"semanticDiagnosticsPerFile":[1,[2,[{"file":"./index.tsx","start":265,"length":9,"messageText":"This JSX tag's 'children' prop expects a single child of type 'never', but multiple children were provided.","category":1,"code":2746},{"file":"./index.tsx","start":265,"length":9,"messageText":"This JSX tag's 'children' prop expects a single child of type 'number | undefined', but multiple children were provided.","category":1,"code":2746},{"file":"./index.tsx","start":265,"length":9,"code":2769,"category":1,"messageText":{"messageText":"No overload matches this call.","category":1,"code":2769,"next":[{"code":2746,"category":1,"messageText":"This JSX tag's 'children' prop expects a single child of type 'never', but multiple children were provided."},{"code":2746,"category":1,"messageText":"This JSX tag's 'children' prop expects a single child of type 'number | undefined', but multiple children were provided."}]},"relatedInformation":[]}]]]},"version":"FakeTSVersion"}
+
+//// [/src/project/tsconfig.tsbuildinfo.readable.baseline.txt]
+{
+  "program": {
+    "fileNames": [
+      "../../lib/lib.d.ts",
+      "./index.tsx"
+    ],
+    "fileInfos": {
+      "../../lib/lib.d.ts": {
+        "version": "7198220534-/// <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; };\ninterface ReadonlyArray<T> { readonly length: number }",
+        "signature": "7198220534-/// <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; };\ninterface ReadonlyArray<T> { readonly length: number }",
+        "affectsGlobalScope": true
+      },
+      "./index.tsx": {
+        "version": "42569361247-declare namespace JSX {\n    interface ElementChildrenAttribute { children: {}; }\n    interface IntrinsicElements { div: {} }\n}\n\ndeclare var React: any;\n\ndeclare function Component(props: never): any;\ndeclare function Component(props: { children?: number }): any;\n(<Component>\n    <div />\n    <div />\n</Component>)",
+        "signature": "42569361247-declare namespace JSX {\n    interface ElementChildrenAttribute { children: {}; }\n    interface IntrinsicElements { div: {} }\n}\n\ndeclare var React: any;\n\ndeclare function Component(props: never): any;\ndeclare function Component(props: { children?: number }): any;\n(<Component>\n    <div />\n    <div />\n</Component>)",
+        "affectsGlobalScope": true
+      }
+    },
+    "options": {
+      "jsx": 2,
+      "module": 99,
+      "strict": true
+    },
+    "referencedMap": {},
+    "exportedModulesMap": {},
+    "semanticDiagnosticsPerFile": [
+      "../../lib/lib.d.ts",
+      [
+        "./index.tsx",
+        [
+          {
+            "file": "./index.tsx",
+            "start": 265,
+            "length": 9,
+            "messageText": "This JSX tag's 'children' prop expects a single child of type 'never', but multiple children were provided.",
+            "category": 1,
+            "code": 2746
+          },
+          {
+            "file": "./index.tsx",
+            "start": 265,
+            "length": 9,
+            "messageText": "This JSX tag's 'children' prop expects a single child of type 'number | undefined', but multiple children were provided.",
+            "category": 1,
+            "code": 2746
+          },
+          {
+            "file": "./index.tsx",
+            "start": 265,
+            "length": 9,
+            "code": 2769,
+            "category": 1,
+            "messageText": {
+              "messageText": "No overload matches this call.",
+              "category": 1,
+              "code": 2769,
+              "next": [
+                {
+                  "code": 2746,
+                  "category": 1,
+                  "messageText": "This JSX tag's 'children' prop expects a single child of type 'never', but multiple children were provided."
+                },
+                {
+                  "code": 2746,
+                  "category": 1,
+                  "messageText": "This JSX tag's 'children' prop expects a single child of type 'number | undefined', but multiple children were provided."
+                }
+              ]
+            },
+            "relatedInformation": []
+          }
+        ]
+      ]
+    ]
+  },
+  "version": "FakeTSVersion",
+  "size": 2053
+}
+
+
+
+Change:: no-change-run
+Input::
+
+
+Output::
+/lib/tsc -p src/project
+src/project/index.tsx:10:3 - error TS2746: This JSX tag's 'children' prop expects a single child of type 'never', but multiple children were provided.
+
+10 (<Component>
+     ~~~~~~~~~
+
+src/project/index.tsx:10:3 - error TS2746: This JSX tag's 'children' prop expects a single child of type 'number | undefined', but multiple children were provided.
+
+10 (<Component>
+     ~~~~~~~~~
+
+src/project/index.tsx:10:3 - error TS2769: No overload matches this call.
+  This JSX tag's 'children' prop expects a single child of type 'never', but multiple children were provided.
+  This JSX tag's 'children' prop expects a single child of type 'number | undefined', but multiple children were provided.
+
+10 (<Component>
+     ~~~~~~~~~
+
+
+
+Found 3 errors in the same file, starting at: src/project/index.tsx:10
+
+exitCode:: ExitStatus.DiagnosticsPresent_OutputsGenerated
+
+