fix: force type alias resolution

mxsdev · Oct 4, 2022 · 293b3bb · 293b3bb
1 parent d5f8b76
commit 293b3bb
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Showing 3 changed files with 49 additions and 5 deletions.
diff --git a/src/merge.ts b/src/merge.ts
@@ -12,9 +12,15 @@ function _recursiveMergeIntersection(typeChecker: ts.TypeChecker, types: ts.Type
 
     const objectTypes: ts.ObjectType[] = []
     const otherTypes: ts.Type[] = []
+    const functionTypes: ts.ObjectType[] = []
     let res: ts.Type
-    
+
     for(const type of types) {
+        const signatures = [
+            ...typeChecker.getSignaturesOfType(type, ts.SignatureKind.Call),
+            ...typeChecker.getSignaturesOfType(type, ts.SignatureKind.Construct),
+        ]
+
         if(type.flags & ts.TypeFlags.Intersection) {
             ;(type as ts.IntersectionType).types.forEach((type) => {
                 if(type.flags & ts.TypeFlags.Object) {
@@ -24,22 +30,39 @@ function _recursiveMergeIntersection(typeChecker: ts.TypeChecker, types: ts.Type
                 }
             })
         } else if(type.flags & ts.TypeFlags.Union) {
-            const newType = createUnionType(typeChecker, ) 
+            const newType = createUnionType(typeChecker) 
             otherTypes.push(newType)
             seen.set(type, newType)
 
             const unionTypeMembers = (type as ts.UnionType).types.map(t => _recursiveMergeIntersection(typeChecker, [t], seen))
             newType.types = unionTypeMembers
         } else if(type.flags & ts.TypeFlags.Object) {
-            objectTypes.push(type as ts.ObjectType)
+            if(signatures.length > 0) {
+                // function type
+                otherTypes.push(type)
+                functionTypes.push(type as ts.ObjectType)
+            } else {
+                objectTypes.push(type as ts.ObjectType)
+            }
         } else {
             otherTypes.push(type)
         }
     }
 
     if(otherTypes.length === 1 && objectTypes.length === 0) {
-        if(types.length === 1) seen.set(types[0], otherTypes[0])
-        return otherTypes[0]
+        // if(functionTypes.length === 1) {
+        //     // generate new function ?
+        //     if(types.length === 1) seen.set(types[0], otherTypes[0])
+        //     return otherTypes[0]
+        // } else {
+        //     if(types.length === 1) seen.set(types[0], otherTypes[0])
+        //     return otherTypes[0]
+        // }
+
+        const newType = cloneTypeWithoutAlias(otherTypes[0])
+        seen.set(otherTypes[0], newType)
+
+        return newType
     } else if(otherTypes.length === 0 && objectTypes.length > 0) {
         const newType = createAnonymousObjectType()
         if(types.length === 1) seen.set(types[0], newType)
@@ -93,4 +116,21 @@ function _recursiveMergeIntersection(typeChecker: ts.TypeChecker, types: ts.Type
 
         return symbol
     }
+
+    function cloneTypeWithoutAlias(type: ts.Type) {
+        type = cloneClassInstance(type)
+
+        const symbol = type.getSymbol()
+
+        if(type.aliasSymbol && symbol) {
+            // remove type alias
+            type.aliasSymbol = undefined
+        }
+
+        return type
+    }
+}
+
+function cloneClassInstance<T>(orig: T): T {
+    return Object.assign(Object.create(Object.getPrototypeOf(orig)), orig) as T
 }
diff --git a/tests/cases/lambda.ts b/tests/cases/lambda.ts
@@ -0,0 +1,2 @@
+type f = (arg1: string, arg2: boolean) => void
+type t = { a: string } | f
diff --git a/tests/lib/baselines.ts b/tests/lib/baselines.ts
@@ -42,6 +42,8 @@ export async function acceptBaselines() {
 }
 
 export async function generateBaselineTests() {
+
+
     const allTestCases = await getTestCases()
 
     describe("baselines", () => {