Add test for type inference

quint/test/types/inferrer.test.ts

@@ -4,6 +4,7 @@ import { TypeInferenceResult, TypeInferrer } from '../../src/types/inferrer'
 import { typeSchemeToString } from '../../src/types/printing'
 import { errorTreeToString } from '../../src/errorTree'
 import { parseMockedModule } from '../util'
+import { moduleToString } from '../../src'
 
 describe('inferTypes', () => {
   function inferTypesForDefs(defs: string[]): TypeInferenceResult {
@@ -134,6 +135,31 @@ describe('inferTypes', () => {
     ])
   })
 
+  it('infers types for variants', () => {
+    const defs = ['type T = A(int) | B', 'val a = variant("A", 3)']
+
+    const [errors, types] = inferTypesForDefs(defs)
+    assert.isEmpty(errors, `Should find no errors, found: ${[...errors.values()].map(errorTreeToString)}`)
+
+    const stringTypes = Array.from(types.entries()).map(([id, type]) => [id, typeSchemeToString(type)])
+    assert.sameDeepMembers(stringTypes, [
+      [14n, 'str'],
+      [15n, 'int'],
+      [16n, '(A(int))'],
+      [17n, '(A(int))'],
+      [10n, 'str'],
+      [11n, '{}'],
+      [12n, '(B({}))'],
+      [13n, '(B({}))'],
+      [5n, 'int'],
+      [4n, 'str'],
+      [6n, 'int'],
+      [7n, '(A(int))'],
+      [8n, '(int) => (A(int))'],
+      [9n, '(int) => (A(int))'],
+    ])
+  })
+
   it('keeps track of free variables in nested scopes (#966)', () => {
     const defs = ['def f(a) = a == "x"', 'def g(b) = val nested = (1,2) { f(b) }']