Comments and utility types

test/programs/comments-from-lib/main.ts

@@ -0,0 +1,12 @@
+/**
+ * Use this comment
+ */
+export type MyObject = Pick<BigThing, "prop1">;
+
+/**
+ * Not this comment though
+ */
+interface BigThing {
+  prop1: string;
+  prop2: string;
+};

test/programs/comments-from-lib/schema.json

@@ -0,0 +1,13 @@
+{
+  "description": "Use this comment",
+  "type": "object",
+  "properties": {
+    "prop1": {
+      "type": "string"
+    }
+  },
+  "required": [
+    "prop1"
+  ],
+  "$schema": "http://json-schema.org/draft-07/schema#"
+}

test/programs/dates/schema.json

@@ -2,12 +2,10 @@
     "$schema": "http://json-schema.org/draft-07/schema#",
     "properties": {
         "var1": {
-            "description": "Enables basic storage and retrieval of dates and times.",
             "format": "date-time",
             "type": "string"
         },
         "var2": {
-            "description": "Enables basic storage and retrieval of dates and times.",
             "format": "date-time",
             "type": "string"
         }

test/programs/type-aliases-partial/schema.json

@@ -15,7 +15,6 @@
   "definitions": {
     "__type": {
       "type": "object",
-      "description": "Make all properties in T optional",
       "properties": {
         "x": {
           "type": "number"
@@ -30,7 +29,6 @@
     },
     "__type_1": {
       "type": "object",
-      "description": "Make all properties in T optional",
       "properties": {
         "a": {
           "type": "number"
@@ -45,4 +43,4 @@
     }
   },
   "$schema": "http://json-schema.org/draft-07/schema#"
-}
+}

test/schema.test.ts

@@ -297,6 +297,7 @@ describe("schema", () => {
         assertSchema("comments-imports", "MyObject", {
             aliasRef: true,
         });
+        assertSchema("comments-from-lib", "MyObject");
     });
 
     describe("types", () => {

typescript-json-schema.ts

@@ -512,6 +512,14 @@ export class JsonSchemaGenerator {
         return this.reffedDefinitions;
     }
 
+    private isFromDefaultLib(symbol: ts.Symbol) {
+        const declarations = symbol.getDeclarations();
+        if (declarations && declarations.length > 0) {
+            return declarations[0].parent.getSourceFile().hasNoDefaultLib;
+        }
+        return false;
+    }
+
     /**
      * Parse the comments of a symbol into the definition and other annotations.
      */
@@ -520,15 +528,17 @@ export class JsonSchemaGenerator {
             return;
         }
 
-        // the comments for a symbol
-        const comments = symbol.getDocumentationComment(this.tc);
+        if (!this.isFromDefaultLib(symbol)) {
+            // the comments for a symbol
+            const comments = symbol.getDocumentationComment(this.tc);
 
-        if (comments.length) {
-            definition.description = comments
-                .map((comment) =>
-                    comment.kind === "lineBreak" ? comment.text : comment.text.trim().replace(/\r\n/g, "\n")
-                )
-                .join("");
+            if (comments.length) {
+                definition.description = comments
+                    .map((comment) =>
+                        comment.kind === "lineBreak" ? comment.text : comment.text.trim().replace(/\r\n/g, "\n")
+                    )
+                    .join("");
+            }
         }
 
         // jsdocs are separate from comments
@@ -1262,6 +1272,10 @@ export class JsonSchemaGenerator {
         if (prop) {
             this.parseCommentsIntoDefinition(prop, returnedDefinition, otherAnnotations);
         }
+        if (pairedSymbol && symbol && this.isFromDefaultLib(symbol)) {
+            this.parseCommentsIntoDefinition(pairedSymbol, definition, otherAnnotations);
+        }
+
         // Create the actual definition only if is an inline definition, or
         // if it will be a $ref and it is not yet created
         if (!asRef || !this.reffedDefinitions[fullTypeName]) {