feat(api): support mapped type parameters

packages/api/src/tree.ts

@@ -1,7 +1,7 @@
 import assert from "assert";
 import ts from "typescript";
 import { IndexInfo, SignatureInfo, SymbolInfo, TypeId, TypeInfo, TypeInfoNoId, TypeParameterInfo } from "./types";
-import { getIntersectionTypesFlat, getSignaturesOfType, getSymbolType, getTypeId, isPureObject, wrapSafe } from "./util";
+import { getIndexInfos, getIntersectionTypesFlat, getSignaturesOfType, getSymbolType, getTypeId, TSIndexInfoMerged, isPureObject, wrapSafe } from "./util";
 
 // TODO: need to add max depth
 
@@ -43,7 +43,9 @@ export function generateTypeTree({ symbol, type }: {symbol: ts.Symbol, type?: un
 function _generateTypeTree(typeChecker: ts.TypeChecker, type: ts.Type, ctx: TypeTreeContext): TypeInfoNoId {
     const flags = type.getFlags()
 
-    if(flags & ts.TypeFlags.Any) { return { kind: 'primitive', primitive: 'any' }}
+    if(flags & ts.TypeFlags.TypeParameter) {
+        return { kind: 'type_parameter'}
+    } else if(flags & ts.TypeFlags.Any) { return { kind: 'primitive', primitive: 'any' }}
     else if(flags & ts.TypeFlags.Unknown) { return { kind: 'primitive', primitive: 'unknown' }}
     else if(flags & ts.TypeFlags.Undefined) { return { kind: 'primitive', primitive: 'undefined' }}
     else if(flags & ts.TypeFlags.Null) { return { kind: 'primitive', primitive: 'null' }}
@@ -64,16 +66,13 @@ function _generateTypeTree(typeChecker: ts.TypeChecker, type: ts.Type, ctx: Type
     // TODO: add enum info???
     else if(flags & ts.TypeFlags.BigIntLiteral) { return { kind: 'bigint_literal', value: (type as ts.BigIntLiteralType).value }}
     // TODO: add type param info
-    else if(flags & ts.TypeFlags.TypeParameter) {
-
-    }
     else if(flags & ts.TypeFlags.Object) {
         // TODO: arrays
         return {
             kind: 'object',
             signatures: getSignaturesOfType(typeChecker, type).map(sig => getSignatureInfo(sig, ctx)),
             properties: type.getProperties().map(typeTreeSymb),
-            indexInfos: typeChecker.getIndexInfosOfType(type).map(indexInfo => getIndexInfo(indexInfo, ctx))
+            indexInfos: getIndexInfos(typeChecker, type).map(indexInfo => getIndexInfo(indexInfo, ctx))
         }
     } else if(flags & ts.TypeFlags.Union) {
         return {
@@ -145,13 +144,14 @@ function getSignatureInfo(signature: ts.Signature, ctx: TypeTreeContext): Signat
     }
 }
 
-function getIndexInfo(indexInfo: ts.IndexInfo, ctx: TypeTreeContext): IndexInfo {
+function getIndexInfo(indexInfo: TSIndexInfoMerged, ctx: TypeTreeContext): IndexInfo {
     const { typeChecker } = ctx
 
     return {
-        keyType: generateTypeTree({ type: indexInfo.keyType }, ctx),
-        type: generateTypeTree({ type: indexInfo.type }, ctx),
-        parameterSymbol: wrapSafe(getSymbolInfo)(wrapSafe(typeChecker.getSymbolAtLocation)(indexInfo.declaration?.parameters[0]))
+        ...indexInfo.keyType ? { keyType: generateTypeTree({ type: indexInfo.keyType }, ctx) } : { },
+        ...indexInfo.type ? { type: generateTypeTree({ type: indexInfo.type }, ctx) } : { },
+        // @ts-expect-error
+        parameterSymbol: wrapSafe(getSymbolInfo)(wrapSafe(typeChecker.getSymbolAtLocation)(indexInfo?.declaration?.parameters?.[0]))
     }
 }
 
@@ -168,7 +168,10 @@ export function getTypeInfoChildren(info: TypeInfo): TypeInfo[] {
             return [
                 ...info.properties,
                 ...info.signatures?.flatMap(s => [...s.parameters, s.returnType]) ?? [],
-                ...info.indexInfos?.map(x => x.type) ?? [],
+                ...info.indexInfos?.flatMap(x => [
+                    ...(x.type ? [x.type] : []),
+                    ...(x.keyType ? [x.keyType] : []),
+                ]) ?? [],
                 // TODO: array
             ]
         }

packages/api/src/types.ts

@@ -6,8 +6,8 @@ export type SymbolInfo = {
 }
 
 export type IndexInfo = {
-    keyType: TypeInfo,
-    type: TypeInfo,
+    keyType?: TypeInfo,
+    type?: TypeInfo,
     parameterSymbol?: SymbolInfo
 }
 

packages/api/src/util.ts

@@ -79,8 +79,33 @@ export function getSignaturesOfType(typeChecker: ts.TypeChecker, type: ts.Type)
     ]
 }
 
+export type TSIndexInfoMerged = { declaration?: ts.MappedTypeNode|ts.IndexSignatureDeclaration, keyType?: ts.Type, type?: ts.Type, parameterType?: ts.Type }
+interface MappedType extends ts.Type {
+    declaration: ts.MappedTypeNode;
+    typeParameter?: ts.TypeParameter;
+    constraintType?: ts.Type;
+    // nameType?: ts.Type;
+    templateType?: ts.Type;
+    modifiersType?: ts.Type;
+    // resolvedApparentType?: ts.Type;
+    // containsError?: boolean;
+}
+
 export function getIndexInfos(typeChecker: ts.TypeChecker, type: ts.Type) {
-    return typeChecker.getIndexInfosOfType(type)
+    const indexInfos: TSIndexInfoMerged[] = [ ...typeChecker.getIndexInfosOfType(type) ]
+
+    if((type.flags & ts.TypeFlags.Object) && ((type as ObjectType).objectFlags & ts.ObjectFlags.Mapped)) {
+        const mappedType = type as MappedType
+
+        indexInfos.push({
+            keyType: mappedType.constraintType,
+             type: mappedType.templateType,
+              parameterType: mappedType.typeParameter,
+               declaration: mappedType.declaration
+        })
+    }
+
+    return indexInfos
 }
 
 export function createType(checker: ts.TypeChecker, flags: ts.TypeFlags) {

tests/baselines/reference/mapped.tree

@@ -1,7 +1,7 @@
 === mapped.ts ===
 
 type mapped = { [index: string]: number }
-> mapped --- {"kind":"object","signatures":[],"properties":[],"indexInfos":[{"keyType":{"kind":"primitive","primitive":"string","id":15},"type":{"kind":"primitive","primitive":"number","id":16}}],"symbolMeta":{"name":"mapped","flags":524288},"id":86}
+> mapped --- {"kind":"object","signatures":[],"properties":[],"indexInfos":[{"keyType":{"kind":"primitive","primitive":"number","id":16}}],"symbolMeta":{"name":"mapped","flags":524288},"id":86}
 > { [index: string]: number }
 > [index: string]: number
 > [index: string]: number

tests/baselines/reference/partial.merged.types

@@ -3,7 +3,7 @@
 type partialUnion = Partial<{a: string}|{b: string}>
 > partialUnion --- { a?: string; } | { b?: string; }
 > Partial<{a: string}|{b: string}>
-> Partial --- {}
+> Partial --- { [P in keyof T]?: T[P]; }
 > {a: string}|{b: string}
 > {a: string}|{b: string}
 > {a: string}|{b: string}

tests/baselines/reference/partial.tree

@@ -1,9 +1,9 @@
 === partial.ts ===
 
 type partialUnion = Partial<{a: string}|{b: string}>
-> partialUnion --- {"kind":"union","types":[{"kind":"object","signatures":[],"properties":[{"kind":"primitive","primitive":"string","symbolMeta":{"name":"a","flags":50331652},"id":15}],"indexInfos":[],"symbolMeta":{"name":"__type","flags":2048},"id":93},{"kind":"object","signatures":[],"properties":[{"kind":"reference","symbolMeta":{"name":"b","flags":50331652},"id":15}],"indexInfos":[],"symbolMeta":{"name":"__type","flags":2048},"id":95}],"symbolMeta":{"name":"partialUnion","flags":524288},"id":97}
+> partialUnion --- {"kind":"union","types":[{"kind":"object","signatures":[],"properties":[{"kind":"primitive","primitive":"string","symbolMeta":{"name":"a","flags":50331652},"id":15}],"indexInfos":[{"keyType":{"kind":"string_literal","value":"a","id":98}}],"symbolMeta":{"name":"__type","flags":2048},"id":93},{"kind":"object","signatures":[],"properties":[{"kind":"reference","symbolMeta":{"name":"b","flags":50331652},"id":15}],"indexInfos":[{"keyType":{"kind":"string_literal","value":"b","id":100}}],"symbolMeta":{"name":"__type","flags":2048},"id":95}],"symbolMeta":{"name":"partialUnion","flags":524288},"id":97}
 > Partial<{a: string}|{b: string}>
-> Partial --- {"kind":"object","signatures":[],"properties":[],"indexInfos":[],"symbolMeta":{"name":"Partial","flags":524288},"id":86}
+> Partial --- {"kind":"object","signatures":[],"properties":[],"indexInfos":[{"keyType":{"kind":"index","indexOf":{"kind":"type_parameter","symbolMeta":{"name":"T","flags":262144},"id":87},"id":89},"type":{"kind":"indexed_access","indexType":{"kind":"type_parameter","symbolMeta":{"name":"P","flags":262144},"id":88},"objectType":{"kind":"reference","symbolMeta":{"name":"T","flags":262144},"id":87},"id":99}}],"symbolMeta":{"name":"Partial","flags":524288},"id":86}
 > {a: string}|{b: string}
 > {a: string}|{b: string}
 > {a: string}|{b: string}

tests/baselines/reference/pick.merged.types

@@ -16,11 +16,11 @@ type t = { a: "b", c: "d", d: { a: "b" } }
 > a --- "b"
 
 type p = Pick<t, "a"|"d"> & {b: "asd", d: { b: "c" }}
-> p --- { d: { a: "b"; b: "c"; }; a: "b"; b: "asd"; }
+> p --- { b: "asd"; d: { b: "c"; }; } & Pick<t, "d" | "a">
 > Pick<t, "a"|"d"> & {b: "asd", d: { b: "c" }}
 > Pick<t, "a"|"d"> & {b: "asd", d: { b: "c" }}
 > Pick<t, "a"|"d">
-> Pick --- {}
+> Pick --- { [P in K]: T[P]; }
 > t, "a"|"d"
 > t
 > t --- { a: "b"; c: "d"; d: { a: "b"; }; }
@@ -39,9 +39,9 @@ const test3: p = {a: "b", b: "asd", d: { a: "b", b: "c" }}
 > const test3: p = {a: "b", b: "asd", d: { a: "b", b: "c" }}
 > test3: p = {a: "b", b: "asd", d: { a: "b", b: "c" }}
 > test3: p = {a: "b", b: "asd", d: { a: "b", b: "c" }}
-> test3 --- { d: { a: "b"; b: "c"; }; a: "b"; b: "asd"; }
+> test3 --- { b: "asd"; d: { b: "c"; }; } & Pick<t, "d" | "a">
 > p
-> p --- { d: { a: "b"; b: "c"; }; a: "b"; b: "asd"; }
+> p --- { b: "asd"; d: { b: "c"; }; } & Pick<t, "d" | "a">
 > {a: "b", b: "asd", d: { a: "b", b: "c" }}
 > a: "b", b: "asd", d: { a: "b", b: "c" }
 > a: "b"

tests/baselines/reference/pick.tree

@@ -16,11 +16,11 @@ type t = { a: "b", c: "d", d: { a: "b" } }
 > a --- {"kind":"string_literal","value":"b","symbolMeta":{"name":"a","flags":4},"id":87}
 
 type p = Pick<t, "a"|"d"> & {b: "asd", d: { b: "c" }}
-> p --- {"kind":"object","properties":[{"kind":"object","properties":[{"kind":"string_literal","value":"b","symbolMeta":{"name":"a","flags":4},"id":87},{"kind":"string_literal","value":"c","symbolMeta":{"name":"b","flags":4},"id":107}],"symbolMeta":{"name":"d","flags":33554436},"id":106},{"kind":"reference","symbolMeta":{"name":"a","flags":33554436},"id":87},{"kind":"string_literal","value":"asd","symbolMeta":{"name":"b","flags":4},"id":109}],"symbolMeta":{"name":"p","flags":524288},"id":103}
+> p --- {"kind":"intersection","types":[{"kind":"object","signatures":[],"properties":[{"kind":"object","signatures":[],"properties":[{"kind":"string_literal","value":"b","symbolMeta":{"name":"a","flags":4},"id":87}],"indexInfos":[],"symbolMeta":{"name":"d","flags":33554436},"id":91},{"kind":"reference","symbolMeta":{"name":"a","flags":33554436},"id":87}],"indexInfos":[{"keyType":{"kind":"union","types":[{"kind":"string_literal","value":"d","id":89},{"kind":"string_literal","value":"a","id":97}],"id":99}}],"symbolMeta":{"name":"__type","flags":2048},"id":100}],"properties":[{"kind":"object","properties":[{"kind":"reference","symbolMeta":{"name":"a","flags":4},"id":87},{"kind":"string_literal","value":"c","symbolMeta":{"name":"b","flags":4},"id":107}],"symbolMeta":{"name":"d","flags":33554436},"id":106},{"kind":"reference","symbolMeta":{"name":"a","flags":33554436},"id":87},{"kind":"string_literal","value":"asd","symbolMeta":{"name":"b","flags":4},"id":109}],"symbolMeta":{"name":"p","flags":524288},"id":103}
 > Pick<t, "a"|"d"> & {b: "asd", d: { b: "c" }}
 > Pick<t, "a"|"d"> & {b: "asd", d: { b: "c" }}
 > Pick<t, "a"|"d">
-> Pick --- {"kind":"object","signatures":[],"properties":[],"indexInfos":[],"symbolMeta":{"name":"Pick","flags":524288},"id":92}
+> Pick --- {"kind":"object","signatures":[],"properties":[],"indexInfos":[{"keyType":{"kind":"type_parameter","symbolMeta":{"name":"K","flags":262144},"id":94},"type":{"kind":"indexed_access","indexType":{"kind":"type_parameter","symbolMeta":{"name":"P","flags":262144},"id":95},"objectType":{"kind":"type_parameter","symbolMeta":{"name":"T","flags":262144},"id":93},"id":104}}],"symbolMeta":{"name":"Pick","flags":524288},"id":92}
 > t, "a"|"d"
 > t
 > t --- {"kind":"object","signatures":[],"properties":[{"kind":"string_literal","value":"b","symbolMeta":{"name":"a","flags":4},"id":87},{"kind":"string_literal","value":"d","symbolMeta":{"name":"c","flags":4},"id":89},{"kind":"object","signatures":[],"properties":[{"kind":"reference","symbolMeta":{"name":"a","flags":4},"id":87}],"indexInfos":[],"symbolMeta":{"name":"d","flags":4},"id":91}],"indexInfos":[],"symbolMeta":{"name":"t","flags":524288},"id":86}
@@ -39,9 +39,9 @@ const test3: p = {a: "b", b: "asd", d: { a: "b", b: "c" }}
 > const test3: p = {a: "b", b: "asd", d: { a: "b", b: "c" }}
 > test3: p = {a: "b", b: "asd", d: { a: "b", b: "c" }}
 > test3: p = {a: "b", b: "asd", d: { a: "b", b: "c" }}
-> test3 --- {"kind":"object","properties":[{"kind":"object","properties":[{"kind":"string_literal","value":"b","symbolMeta":{"name":"a","flags":4},"id":87},{"kind":"string_literal","value":"c","symbolMeta":{"name":"b","flags":4},"id":107}],"symbolMeta":{"name":"d","flags":33554436},"id":106},{"kind":"reference","symbolMeta":{"name":"a","flags":33554436},"id":87},{"kind":"string_literal","value":"asd","symbolMeta":{"name":"b","flags":4},"id":109}],"symbolMeta":{"name":"test3","flags":2},"id":103}
+> test3 --- {"kind":"intersection","types":[{"kind":"object","signatures":[],"properties":[{"kind":"object","signatures":[],"properties":[{"kind":"string_literal","value":"b","symbolMeta":{"name":"a","flags":4},"id":87}],"indexInfos":[],"symbolMeta":{"name":"d","flags":33554436},"id":91},{"kind":"reference","symbolMeta":{"name":"a","flags":33554436},"id":87}],"indexInfos":[{"keyType":{"kind":"union","types":[{"kind":"string_literal","value":"d","id":89},{"kind":"string_literal","value":"a","id":97}],"id":99}}],"symbolMeta":{"name":"__type","flags":2048},"id":100}],"properties":[{"kind":"object","properties":[{"kind":"reference","symbolMeta":{"name":"a","flags":4},"id":87},{"kind":"string_literal","value":"c","symbolMeta":{"name":"b","flags":4},"id":107}],"symbolMeta":{"name":"d","flags":33554436},"id":106},{"kind":"reference","symbolMeta":{"name":"a","flags":33554436},"id":87},{"kind":"string_literal","value":"asd","symbolMeta":{"name":"b","flags":4},"id":109}],"symbolMeta":{"name":"test3","flags":2},"id":103}
 > p
-> p --- {"kind":"object","properties":[{"kind":"object","properties":[{"kind":"string_literal","value":"b","symbolMeta":{"name":"a","flags":4},"id":87},{"kind":"string_literal","value":"c","symbolMeta":{"name":"b","flags":4},"id":107}],"symbolMeta":{"name":"d","flags":33554436},"id":106},{"kind":"reference","symbolMeta":{"name":"a","flags":33554436},"id":87},{"kind":"string_literal","value":"asd","symbolMeta":{"name":"b","flags":4},"id":109}],"symbolMeta":{"name":"p","flags":524288},"id":103}
+> p --- {"kind":"intersection","types":[{"kind":"object","signatures":[],"properties":[{"kind":"object","signatures":[],"properties":[{"kind":"string_literal","value":"b","symbolMeta":{"name":"a","flags":4},"id":87}],"indexInfos":[],"symbolMeta":{"name":"d","flags":33554436},"id":91},{"kind":"reference","symbolMeta":{"name":"a","flags":33554436},"id":87}],"indexInfos":[{"keyType":{"kind":"union","types":[{"kind":"string_literal","value":"d","id":89},{"kind":"string_literal","value":"a","id":97}],"id":99}}],"symbolMeta":{"name":"__type","flags":2048},"id":100}],"properties":[{"kind":"object","properties":[{"kind":"reference","symbolMeta":{"name":"a","flags":4},"id":87},{"kind":"string_literal","value":"c","symbolMeta":{"name":"b","flags":4},"id":107}],"symbolMeta":{"name":"d","flags":33554436},"id":106},{"kind":"reference","symbolMeta":{"name":"a","flags":33554436},"id":87},{"kind":"string_literal","value":"asd","symbolMeta":{"name":"b","flags":4},"id":109}],"symbolMeta":{"name":"p","flags":524288},"id":103}
 > {a: "b", b: "asd", d: { a: "b", b: "c" }}
 > a: "b", b: "asd", d: { a: "b", b: "c" }
 > a: "b"