Accepted baselines.

tests/baselines/reference/api/tsserverlibrary.d.ts

@@ -2868,6 +2868,7 @@ declare namespace ts {
         suppressImplicitAnyIndexErrors?: boolean;
         target?: ScriptTarget;
         traceResolution?: boolean;
+        useUnknownInCatchVariables?: boolean;
         resolveJsonModule?: boolean;
         types?: string[];
         /** Paths used to compute primary types search locations */

tests/baselines/reference/api/typescript.d.ts

@@ -2868,6 +2868,7 @@ declare namespace ts {
         suppressImplicitAnyIndexErrors?: boolean;
         target?: ScriptTarget;
         traceResolution?: boolean;
+        useUnknownInCatchVariables?: boolean;
         resolveJsonModule?: boolean;
         types?: string[];
         /** Paths used to compute primary types search locations */

tests/baselines/reference/showConfig/Shows tsconfig for single option/useUnknownInCatchVariables/tsconfig.json

@@ -0,0 +1,5 @@
+{
+    "compilerOptions": {
+        "useUnknownInCatchVariables": true
+    }
+}

tests/baselines/reference/tsConfig/Default initialized TSConfig/tsconfig.json

@@ -41,6 +41,7 @@
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tsConfig/Initialized TSConfig with advanced options/tsconfig.json

@@ -41,6 +41,7 @@
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tsConfig/Initialized TSConfig with boolean value compiler options/tsconfig.json

@@ -41,6 +41,7 @@
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tsConfig/Initialized TSConfig with enum value compiler options/tsconfig.json

@@ -41,6 +41,7 @@
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tsConfig/Initialized TSConfig with files options/tsconfig.json

@@ -41,6 +41,7 @@
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tsConfig/Initialized TSConfig with incorrect compiler option value/tsconfig.json

@@ -41,6 +41,7 @@
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tsConfig/Initialized TSConfig with incorrect compiler option/tsconfig.json

@@ -41,6 +41,7 @@
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tsConfig/Initialized TSConfig with list compiler options with enum value/tsconfig.json

@@ -41,6 +41,7 @@
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tsConfig/Initialized TSConfig with list compiler options/tsconfig.json

@@ -41,6 +41,7 @@
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/declarationDir-is-specified.js

@@ -62,6 +62,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/when-outDir-and-declarationDir-is-specified.js

@@ -62,6 +62,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/when-outDir-is-specified.js

@@ -62,6 +62,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/with-outFile.js

@@ -62,6 +62,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/without-outDir-or-outFile-is-specified-with-declaration-enabled.js

@@ -62,6 +62,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/tscWatch/programUpdates/should-not-trigger-recompilation-because-of-program-emit/without-outDir-or-outFile-is-specified.js

@@ -62,6 +62,7 @@ interface Array<T> { length: number; [n: number]: T; }
     // "noFallthroughCasesInSwitch": true,          /* Report errors for fallthrough cases in switch statement. */
     // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
     // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */
+    // "useUnknownInCatchVariables": true,          /* Type catch clause variables as 'unknown' instead of 'any'. */
 
     /* Module Resolution Options */
     // "moduleResolution": "node",                  /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */

tests/baselines/reference/useUnknownInCatchVariables01.errors.txt

@@ -0,0 +1,35 @@
+tests/cases/compiler/useUnknownInCatchVariables01.ts(6,12): error TS2339: Property 'toUpperCase' does not exist on type 'unknown'.
+tests/cases/compiler/useUnknownInCatchVariables01.ts(7,10): error TS2356: An arithmetic operand must be of type 'any', 'number', 'bigint' or an enum type.
+tests/cases/compiler/useUnknownInCatchVariables01.ts(8,10): error TS2349: This expression is not callable.
+  Type '{}' has no call signatures.
+
+
+==== tests/cases/compiler/useUnknownInCatchVariables01.ts (3 errors) ====
+    try {
+        // ...
+    }
+    catch (e) {
+        // error!
+        void e.toUpperCase();
+               ~~~~~~~~~~~
+!!! error TS2339: Property 'toUpperCase' does not exist on type 'unknown'.
+        void e++;
+             ~
+!!! error TS2356: An arithmetic operand must be of type 'any', 'number', 'bigint' or an enum type.
+        void e();
+             ~
+!!! error TS2349: This expression is not callable.
+!!! error TS2349:   Type '{}' has no call signatures.
+    
+        if (typeof e === "string") {
+            // works!
+            // We've narrowed 'e' down to the type 'string'.
+            console.log(e.toUpperCase());
+        }
+        if (e instanceof Error) {
+            e.stack?.toUpperCase();
+        }
+        if (typeof e === "number") {
+            e++;
+        }
+    }

tests/baselines/reference/useUnknownInCatchVariables01.js

@@ -0,0 +1,45 @@
+//// [useUnknownInCatchVariables01.ts]
+try {
+    // ...
+}
+catch (e) {
+    // error!
+    void e.toUpperCase();
+    void e++;
+    void e();
+
+    if (typeof e === "string") {
+        // works!
+        // We've narrowed 'e' down to the type 'string'.
+        console.log(e.toUpperCase());
+    }
+    if (e instanceof Error) {
+        e.stack?.toUpperCase();
+    }
+    if (typeof e === "number") {
+        e++;
+    }
+}
+
+//// [useUnknownInCatchVariables01.js]
+var _a;
+try {
+    // ...
+}
+catch (e) {
+    // error!
+    void e.toUpperCase();
+    void e++;
+    void e();
+    if (typeof e === "string") {
+        // works!
+        // We've narrowed 'e' down to the type 'string'.
+        console.log(e.toUpperCase());
+    }
+    if (e instanceof Error) {
+        (_a = e.stack) === null || _a === void 0 ? void 0 : _a.toUpperCase();
+    }
+    if (typeof e === "number") {
+        e++;
+    }
+}

tests/baselines/reference/useUnknownInCatchVariables01.symbols

@@ -0,0 +1,48 @@
+=== tests/cases/compiler/useUnknownInCatchVariables01.ts ===
+try {
+    // ...
+}
+catch (e) {
+>e : Symbol(e, Decl(useUnknownInCatchVariables01.ts, 3, 7))
+
+    // error!
+    void e.toUpperCase();
+>e : Symbol(e, Decl(useUnknownInCatchVariables01.ts, 3, 7))
+
+    void e++;
+>e : Symbol(e, Decl(useUnknownInCatchVariables01.ts, 3, 7))
+
+    void e();
+>e : Symbol(e, Decl(useUnknownInCatchVariables01.ts, 3, 7))
+
+    if (typeof e === "string") {
+>e : Symbol(e, Decl(useUnknownInCatchVariables01.ts, 3, 7))
+
+        // works!
+        // We've narrowed 'e' down to the type 'string'.
+        console.log(e.toUpperCase());
+>console.log : Symbol(Console.log, Decl(lib.dom.d.ts, --, --))
+>console : Symbol(console, Decl(lib.dom.d.ts, --, --))
+>log : Symbol(Console.log, Decl(lib.dom.d.ts, --, --))
+>e.toUpperCase : Symbol(String.toUpperCase, Decl(lib.es5.d.ts, --, --))
+>e : Symbol(e, Decl(useUnknownInCatchVariables01.ts, 3, 7))
+>toUpperCase : Symbol(String.toUpperCase, Decl(lib.es5.d.ts, --, --))
+    }
+    if (e instanceof Error) {
+>e : Symbol(e, Decl(useUnknownInCatchVariables01.ts, 3, 7))
+>Error : Symbol(Error, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
+
+        e.stack?.toUpperCase();
+>e.stack?.toUpperCase : Symbol(String.toUpperCase, Decl(lib.es5.d.ts, --, --))
+>e.stack : Symbol(Error.stack, Decl(lib.es5.d.ts, --, --))
+>e : Symbol(e, Decl(useUnknownInCatchVariables01.ts, 3, 7))
+>stack : Symbol(Error.stack, Decl(lib.es5.d.ts, --, --))
+>toUpperCase : Symbol(String.toUpperCase, Decl(lib.es5.d.ts, --, --))
+    }
+    if (typeof e === "number") {
+>e : Symbol(e, Decl(useUnknownInCatchVariables01.ts, 3, 7))
+
+        e++;
+>e : Symbol(e, Decl(useUnknownInCatchVariables01.ts, 3, 7))
+    }
+}

tests/baselines/reference/useUnknownInCatchVariables01.types

@@ -0,0 +1,67 @@
+=== tests/cases/compiler/useUnknownInCatchVariables01.ts ===
+try {
+    // ...
+}
+catch (e) {
+>e : unknown
+
+    // error!
+    void e.toUpperCase();
+>void e.toUpperCase() : undefined
+>e.toUpperCase() : any
+>e.toUpperCase : any
+>e : unknown
+>toUpperCase : any
+
+    void e++;
+>void e++ : undefined
+>e++ : number
+>e : unknown
+
+    void e();
+>void e() : undefined
+>e() : any
+>e : unknown
+
+    if (typeof e === "string") {
+>typeof e === "string" : boolean
+>typeof e : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>e : unknown
+>"string" : "string"
+
+        // works!
+        // We've narrowed 'e' down to the type 'string'.
+        console.log(e.toUpperCase());
+>console.log(e.toUpperCase()) : void
+>console.log : (...data: any[]) => void
+>console : Console
+>log : (...data: any[]) => void
+>e.toUpperCase() : string
+>e.toUpperCase : () => string
+>e : string
+>toUpperCase : () => string
+    }
+    if (e instanceof Error) {
+>e instanceof Error : boolean
+>e : unknown
+>Error : ErrorConstructor
+
+        e.stack?.toUpperCase();
+>e.stack?.toUpperCase() : string
+>e.stack?.toUpperCase : () => string
+>e.stack : string
+>e : Error
+>stack : string
+>toUpperCase : () => string
+    }
+    if (typeof e === "number") {
+>typeof e === "number" : boolean
+>typeof e : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>e : unknown
+>"number" : "number"
+
+        e++;
+>e++ : number
+>e : number
+    }
+}