Deprecate import assert in favor of import with

src/compiler/checker.ts

@@ -48552,6 +48552,10 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                 return grammarErrorOnFirstToken(node, Diagnostics.Import_assertions_have_been_replaced_by_import_attributes_Use_with_instead_of_assert);
             }
 
+            if (!isImportAttributes && compilerOptions.ignoreDeprecations !== "6.0") {
+                grammarErrorOnFirstToken(node, Diagnostics.Import_assertions_have_been_replaced_by_import_attributes_Use_with_instead_of_assert);
+            }
+
             if (declaration.moduleSpecifier && getEmitSyntaxForModuleSpecifierExpression(declaration.moduleSpecifier) === ModuleKind.CommonJS) {
                 return grammarErrorOnNode(
                     node,

tests/baselines/reference/getOccurrencesNonStringImportAssertion.baseline.jsonc

@@ -1,4 +1,4 @@
 // === documentHighlights ===
 // === /tests/cases/fourslash/getOccurrencesNonStringImportAssertion.ts ===
-// import * as react from "react" assert { cache: /*HIGHLIGHTS*/0 };
+// import * as react from "react" with { cache: /*HIGHLIGHTS*/0 };
 // react.Children;

tests/baselines/reference/importAssertion1(module=commonjs).errors.txt

@@ -1,8 +1,8 @@
-1.ts(1,14): error TS2821: Import assertions are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
-1.ts(2,28): error TS2821: Import assertions are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
-1.ts(3,28): error TS2821: Import assertions are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
-2.ts(1,28): error TS2821: Import assertions are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
-2.ts(2,38): error TS2821: Import assertions are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
+1.ts(1,14): error TS2823: Import attributes are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
+1.ts(2,28): error TS2823: Import attributes are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
+1.ts(3,28): error TS2823: Import attributes are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
+2.ts(1,28): error TS2823: Import attributes are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
+2.ts(2,38): error TS2823: Import attributes are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
 3.ts(2,25): error TS1324: Dynamic imports only support a second argument when the '--module' option is set to 'esnext', 'node16', 'node18', 'node20', 'nodenext', or 'preserve'.
 3.ts(3,25): error TS1324: Dynamic imports only support a second argument when the '--module' option is set to 'esnext', 'node16', 'node18', 'node20', 'nodenext', or 'preserve'.
 3.ts(4,25): error TS1324: Dynamic imports only support a second argument when the '--module' option is set to 'esnext', 'node16', 'node18', 'node20', 'nodenext', or 'preserve'.
@@ -11,50 +11,50 @@
 3.ts(8,11): message TS1450: Dynamic imports can only accept a module specifier and an optional set of attributes as arguments
 3.ts(9,25): error TS1324: Dynamic imports only support a second argument when the '--module' option is set to 'esnext', 'node16', 'node18', 'node20', 'nodenext', or 'preserve'.
 3.ts(10,25): error TS1324: Dynamic imports only support a second argument when the '--module' option is set to 'esnext', 'node16', 'node18', 'node20', 'nodenext', or 'preserve'.
-3.ts(10,52): error TS1009: Trailing comma not allowed.
+3.ts(10,50): error TS1009: Trailing comma not allowed.
 
 
 ==== 0.ts (0 errors) ====
     export const a = 1;
     export const b = 2;
 
 ==== 1.ts (3 errors) ====
-    import './0' assert { type: "json" }
-                 ~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2821: Import assertions are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
-    import { a, b } from './0' assert { "type": "json" }
-                               ~~~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2821: Import assertions are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
-    import * as foo from './0' assert { type: "json" }
+    import './0' with { type: "json" }
+                 ~~~~~~~~~~~~~~~~~~~~~
+!!! error TS2823: Import attributes are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
+    import { a, b } from './0' with { "type": "json" }
                                ~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2821: Import assertions are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
+!!! error TS2823: Import attributes are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
+    import * as foo from './0' with { type: "json" }
+                               ~~~~~~~~~~~~~~~~~~~~~
+!!! error TS2823: Import attributes are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
     a;
     b;
     foo.a;
     foo.b;
 
 ==== 2.ts (2 errors) ====
-    import { a, b } from './0' assert {}
-                               ~~~~~~~~~
-!!! error TS2821: Import assertions are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
-    import { a as c, b as d } from './0' assert { a: "a", b: "b", c: "c" }
-                                         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2821: Import assertions are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
+    import { a, b } from './0' with {}
+                               ~~~~~~~
+!!! error TS2823: Import attributes are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
+    import { a as c, b as d } from './0' with { a: "a", b: "b", c: "c" }
+                                         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+!!! error TS2823: Import attributes are only supported when the '--module' option is set to 'esnext', 'node18', 'node20', 'nodenext', or 'preserve'.
     a;
     b;
     c;
     d;
 
 ==== 3.ts (9 errors) ====
     const a = import('./0')
-    const b = import('./0', { assert: { type: "json" } })
-                            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+    const b = import('./0', { with: { type: "json" } })
+                            ~~~~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS1324: Dynamic imports only support a second argument when the '--module' option is set to 'esnext', 'node16', 'node18', 'node20', 'nodenext', or 'preserve'.
-    const c = import('./0', { assert: { type: "json", ttype: "typo" } })
-                            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+    const c = import('./0', { with: { type: "json", ttype: "typo" } })
+                            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS1324: Dynamic imports only support a second argument when the '--module' option is set to 'esnext', 'node16', 'node18', 'node20', 'nodenext', or 'preserve'.
-    const d = import('./0', { assert: {} })
-                            ~~~~~~~~~~~~~~
+    const d = import('./0', { with: {} })
+                            ~~~~~~~~~~~~
 !!! error TS1324: Dynamic imports only support a second argument when the '--module' option is set to 'esnext', 'node16', 'node18', 'node20', 'nodenext', or 'preserve'.
     const dd = import('./0', {})
                              ~~
@@ -69,10 +69,10 @@
     const g = import('./0', {}, {})
                             ~~
 !!! error TS1324: Dynamic imports only support a second argument when the '--module' option is set to 'esnext', 'node16', 'node18', 'node20', 'nodenext', or 'preserve'.
-    const h = import('./0', { assert: { type: "json" }},)
-                            ~~~~~~~~~~~~~~~~~~~~~~~~~~~
+    const h = import('./0', { with: { type: "json" }},)
+                            ~~~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS1324: Dynamic imports only support a second argument when the '--module' option is set to 'esnext', 'node16', 'node18', 'node20', 'nodenext', or 'preserve'.
-                                                       ~
+                                                     ~
 !!! error TS1009: Trailing comma not allowed.
 
 

tests/baselines/reference/importAssertion1(module=commonjs).js

@@ -5,33 +5,33 @@ export const a = 1;
 export const b = 2;
 
 //// [1.ts]
-import './0' assert { type: "json" }
-import { a, b } from './0' assert { "type": "json" }
-import * as foo from './0' assert { type: "json" }
+import './0' with { type: "json" }
+import { a, b } from './0' with { "type": "json" }
+import * as foo from './0' with { type: "json" }
 a;
 b;
 foo.a;
 foo.b;
 
 //// [2.ts]
-import { a, b } from './0' assert {}
-import { a as c, b as d } from './0' assert { a: "a", b: "b", c: "c" }
+import { a, b } from './0' with {}
+import { a as c, b as d } from './0' with { a: "a", b: "b", c: "c" }
 a;
 b;
 c;
 d;
 
 //// [3.ts]
 const a = import('./0')
-const b = import('./0', { assert: { type: "json" } })
-const c = import('./0', { assert: { type: "json", ttype: "typo" } })
-const d = import('./0', { assert: {} })
+const b = import('./0', { with: { type: "json" } })
+const c = import('./0', { with: { type: "json", ttype: "typo" } })
+const d = import('./0', { with: {} })
 const dd = import('./0', {})
 declare function foo(): any;
 const e = import('./0', foo())
 const f = import()
 const g = import('./0', {}, {})
-const h = import('./0', { assert: { type: "json" }},)
+const h = import('./0', { with: { type: "json" }},)
 
 
 

tests/baselines/reference/importAssertion1(module=commonjs).symbols

@@ -8,12 +8,12 @@ export const b = 2;
 >b : Symbol(b, Decl(0.ts, 1, 12))
 
 === 1.ts ===
-import './0' assert { type: "json" }
-import { a, b } from './0' assert { "type": "json" }
+import './0' with { type: "json" }
+import { a, b } from './0' with { "type": "json" }
 >a : Symbol(a, Decl(1.ts, 1, 8))
 >b : Symbol(b, Decl(1.ts, 1, 11))
 
-import * as foo from './0' assert { type: "json" }
+import * as foo from './0' with { type: "json" }
 >foo : Symbol(foo, Decl(1.ts, 2, 6))
 
 a;
@@ -33,11 +33,11 @@ foo.b;
 >b : Symbol(b, Decl(0.ts, 1, 12))
 
 === 2.ts ===
-import { a, b } from './0' assert {}
+import { a, b } from './0' with {}
 >a : Symbol(a, Decl(2.ts, 0, 8))
 >b : Symbol(b, Decl(2.ts, 0, 11))
 
-import { a as c, b as d } from './0' assert { a: "a", b: "b", c: "c" }
+import { a as c, b as d } from './0' with { a: "a", b: "b", c: "c" }
 >a : Symbol(a, Decl(0.ts, 0, 12))
 >c : Symbol(c, Decl(2.ts, 1, 8))
 >b : Symbol(b, Decl(0.ts, 1, 12))
@@ -60,23 +60,23 @@ const a = import('./0')
 >a : Symbol(a, Decl(3.ts, 0, 5))
 >'./0' : Symbol("0", Decl(0.ts, 0, 0))
 
-const b = import('./0', { assert: { type: "json" } })
+const b = import('./0', { with: { type: "json" } })
 >b : Symbol(b, Decl(3.ts, 1, 5))
 >'./0' : Symbol("0", Decl(0.ts, 0, 0))
->assert : Symbol(assert, Decl(3.ts, 1, 25))
->type : Symbol(type, Decl(3.ts, 1, 35))
+>with : Symbol(with, Decl(3.ts, 1, 25))
+>type : Symbol(type, Decl(3.ts, 1, 33))
 
-const c = import('./0', { assert: { type: "json", ttype: "typo" } })
+const c = import('./0', { with: { type: "json", ttype: "typo" } })
 >c : Symbol(c, Decl(3.ts, 2, 5))
 >'./0' : Symbol("0", Decl(0.ts, 0, 0))
->assert : Symbol(assert, Decl(3.ts, 2, 25))
->type : Symbol(type, Decl(3.ts, 2, 35))
->ttype : Symbol(ttype, Decl(3.ts, 2, 49))
+>with : Symbol(with, Decl(3.ts, 2, 25))
+>type : Symbol(type, Decl(3.ts, 2, 33))
+>ttype : Symbol(ttype, Decl(3.ts, 2, 47))
 
-const d = import('./0', { assert: {} })
+const d = import('./0', { with: {} })
 >d : Symbol(d, Decl(3.ts, 3, 5))
 >'./0' : Symbol("0", Decl(0.ts, 0, 0))
->assert : Symbol(assert, Decl(3.ts, 3, 25))
+>with : Symbol(with, Decl(3.ts, 3, 25))
 
 const dd = import('./0', {})
 >dd : Symbol(dd, Decl(3.ts, 4, 5))
@@ -97,10 +97,10 @@ const g = import('./0', {}, {})
 >g : Symbol(g, Decl(3.ts, 8, 5))
 >'./0' : Symbol("0", Decl(0.ts, 0, 0))
 
-const h = import('./0', { assert: { type: "json" }},)
+const h = import('./0', { with: { type: "json" }},)
 >h : Symbol(h, Decl(3.ts, 9, 5))
 >'./0' : Symbol("0", Decl(0.ts, 0, 0))
->assert : Symbol(assert, Decl(3.ts, 9, 25))
->type : Symbol(type, Decl(3.ts, 9, 35))
+>with : Symbol(with, Decl(3.ts, 9, 25))
+>type : Symbol(type, Decl(3.ts, 9, 33))
 
 

tests/baselines/reference/importAssertion1(module=commonjs).types

@@ -14,17 +14,17 @@ export const b = 2;
 >  : ^
 
 === 1.ts ===
-import './0' assert { type: "json" }
+import './0' with { type: "json" }
 >type : any
 >     : ^^^
 
-import { a, b } from './0' assert { "type": "json" }
+import { a, b } from './0' with { "type": "json" }
 >a : 1
 >  : ^
 >b : 2
 >  : ^
 
-import * as foo from './0' assert { type: "json" }
+import * as foo from './0' with { type: "json" }
 >foo : typeof foo
 >    : ^^^^^^^^^^
 >type : any
@@ -55,13 +55,13 @@ foo.b;
 >  : ^
 
 === 2.ts ===
-import { a, b } from './0' assert {}
+import { a, b } from './0' with {}
 >a : 1
 >  : ^
 >b : 2
 >  : ^
 
-import { a as c, b as d } from './0' assert { a: "a", b: "b", c: "c" }
+import { a as c, b as d } from './0' with { a: "a", b: "b", c: "c" }
 >a : 1
 >  : ^
 >c : 1
@@ -102,35 +102,35 @@ const a = import('./0')
 >'./0' : "./0"
 >      : ^^^^^
 
-const b = import('./0', { assert: { type: "json" } })
+const b = import('./0', { with: { type: "json" } })
 >b : Promise<typeof import("0")>
 >  : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
->import('./0', { assert: { type: "json" } }) : Promise<typeof import("0")>
->                                            : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+>import('./0', { with: { type: "json" } }) : Promise<typeof import("0")>
+>                                          : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 >'./0' : "./0"
 >      : ^^^^^
->{ assert: { type: "json" } } : { assert: { type: string; }; }
->                             : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
->assert : { type: string; }
->       : ^^^^^^^^^^^^^^^^^
+>{ with: { type: "json" } } : { with: { type: string; }; }
+>                           : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+>with : { type: string; }
+>     : ^^^^^^^^^^^^^^^^^
 >{ type: "json" } : { type: string; }
 >                 : ^^^^^^^^^^^^^^^^^
 >type : string
 >     : ^^^^^^
 >"json" : "json"
 >       : ^^^^^^
 
-const c = import('./0', { assert: { type: "json", ttype: "typo" } })
+const c = import('./0', { with: { type: "json", ttype: "typo" } })
 >c : Promise<typeof import("0")>
 >  : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
->import('./0', { assert: { type: "json", ttype: "typo" } }) : Promise<typeof import("0")>
->                                                           : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+>import('./0', { with: { type: "json", ttype: "typo" } }) : Promise<typeof import("0")>
+>                                                         : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 >'./0' : "./0"
 >      : ^^^^^
->{ assert: { type: "json", ttype: "typo" } } : { assert: { type: string; ttype: string; }; }
->                                            : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
->assert : { type: string; ttype: string; }
->       : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+>{ with: { type: "json", ttype: "typo" } } : { with: { type: string; ttype: string; }; }
+>                                          : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+>with : { type: string; ttype: string; }
+>     : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 >{ type: "json", ttype: "typo" } : { type: string; ttype: string; }
 >                                : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 >type : string
@@ -142,17 +142,17 @@ const c = import('./0', { assert: { type: "json", ttype: "typo" } })
 >"typo" : "typo"
 >       : ^^^^^^
 
-const d = import('./0', { assert: {} })
+const d = import('./0', { with: {} })
 >d : Promise<typeof import("0")>
 >  : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
->import('./0', { assert: {} }) : Promise<typeof import("0")>
->                              : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+>import('./0', { with: {} }) : Promise<typeof import("0")>
+>                            : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 >'./0' : "./0"
 >      : ^^^^^
->{ assert: {} } : { assert: {}; }
->               : ^^^^^^^^^^^^^^^
->assert : {}
->       : ^^
+>{ with: {} } : { with: {}; }
+>             : ^^^^^^^^^^^^^
+>with : {}
+>     : ^^
 >{} : {}
 >   : ^^
 
@@ -200,17 +200,17 @@ const g = import('./0', {}, {})
 >{} : {}
 >   : ^^
 
-const h = import('./0', { assert: { type: "json" }},)
+const h = import('./0', { with: { type: "json" }},)
 >h : Promise<typeof import("0")>
 >  : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
->import('./0', { assert: { type: "json" }},) : Promise<typeof import("0")>
->                                            : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+>import('./0', { with: { type: "json" }},) : Promise<typeof import("0")>
+>                                          : ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 >'./0' : "./0"
 >      : ^^^^^
->{ assert: { type: "json" }} : { assert: { type: string; }; }
->                            : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
->assert : { type: string; }
->       : ^^^^^^^^^^^^^^^^^
+>{ with: { type: "json" }} : { with: { type: string; }; }
+>                          : ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+>with : { type: string; }
+>     : ^^^^^^^^^^^^^^^^^
 >{ type: "json" } : { type: string; }
 >                 : ^^^^^^^^^^^^^^^^^
 >type : string