JS: Make jump-to-def behave nicer

Author: asgerf

javascript/ql/lib/definitions.qll

@@ -153,17 +153,7 @@ private predicate jsdocTypeLookup(JSDocNamedTypeExpr ref, AstNode decl, string k
   kind = "T"
 }
 
-/**
- * Gets an element, of kind `kind`, that element `e` uses, if any.
- *
- * The `kind` is a string representing what kind of use it is:
- *  - `"M"` for function and method calls
- *  - `"T"` for uses of types
- *  - `"V"` for variable accesses
- *  - `"I"` for imports
- */
-cached
-AstNode definitionOf(Locatable e, string kind) {
+private AstNode definitionOfRaw(Locatable e, string kind) {
   variableDefLookup(e, result, kind)
   or
   // prefer definitions over declarations
@@ -179,3 +169,41 @@ AstNode definitionOf(Locatable e, string kind) {
   or
   jsdocTypeLookup(e, result, kind)
 }
+
+/** Gets a more useful node to show for something that resolves to `node`. */
+private AstNode redirectOnce(AstNode node) {
+  exists(ConstructorDeclaration ctor |
+    ctor.isSynthetic() and
+    node = ctor.getBody() and
+    result = ctor.getDeclaringClass()
+  )
+  or
+  exists(ClassDefinition cls |
+    node = cls and
+    result = cls.getIdentifier()
+  )
+  or
+  exists(MethodDeclaration member |
+    not member instanceof ConstructorDeclaration and
+    node = member.getBody() and
+    result = member.getNameExpr()
+  )
+}
+
+private AstNode redirect(AstNode node) {
+  node = definitionOfRaw(_, _) and
+  result = redirectOnce*(node) and
+  not exists(redirectOnce(result))
+}
+
+/**
+ * Gets an element, of kind `kind`, that element `e` uses, if any.
+ *
+ * The `kind` is a string representing what kind of use it is:
+ *  - `"M"` for function and method calls
+ *  - `"T"` for uses of types
+ *  - `"V"` for variable accesses
+ *  - `"I"` for imports
+ */
+cached
+AstNode definitionOf(Locatable e, string kind) { result = redirect(definitionOfRaw(e, kind)) }

javascript/ql/test/library-tests/DataFlow/tests.expected

@@ -1514,6 +1514,7 @@ sources
 | tst2.ts:7:1:9:1 | return of function setX |
 | tst2.ts:8:3:8:5 | A.x |
 | tst2.ts:11:11:11:13 | A.x |
+| tst2.ts:11:11:11:23 | A.x as number |
 | tst2.ts:13:1:13:40 | class S ... ing> {} |
 | tst2.ts:13:26:13:29 | List |
 | tst2.ts:13:39:13:38 | (...arg ... rgs); } |

javascript/ql/test/query-tests/definitions/definitions.expected

@@ -2,22 +2,22 @@
 | b.js:7:1:7:1 | f | b.js:1:1:5:1 | functio ... ar x;\\n} | M |
 | b.js:8:1:8:1 | g | a.js:2:1:2:15 | function g() {} | M |
 | client.ts:1:22:1:30 | "./tslib" | tslib.ts:1:1:10:0 | <toplevel> | I |
-| client.ts:7:19:7:19 | C | tslib.ts:1:8:3:1 | class C {\\n  m() {}\\n} | T |
-| client.ts:8:10:8:10 | C | client.ts:3:1:5:1 | class C {\\n  m() {}\\n} | T |
-| client.ts:9:16:9:16 | C | client.ts:3:1:5:1 | class C {\\n  m() {}\\n} | T |
-| client.ts:10:16:10:16 | C | tslib.ts:6:10:8:3 | class C ...  {}\\n  } | T |
-| client.ts:13:25:13:25 | C | client.ts:3:1:5:1 | class C {\\n  m() {}\\n} | T |
-| client.ts:13:35:13:35 | C | tslib.ts:1:8:3:1 | class C {\\n  m() {}\\n} | T |
-| client.ts:13:47:13:47 | C | tslib.ts:6:10:8:3 | class C ...  {}\\n  } | T |
+| client.ts:7:19:7:19 | C | tslib.ts:1:14:1:14 | C | T |
+| client.ts:8:10:8:10 | C | client.ts:3:7:3:7 | C | T |
+| client.ts:9:16:9:16 | C | client.ts:3:7:3:7 | C | T |
+| client.ts:10:16:10:16 | C | tslib.ts:6:16:6:16 | C | T |
+| client.ts:13:25:13:25 | C | client.ts:3:7:3:7 | C | T |
+| client.ts:13:35:13:35 | C | tslib.ts:1:14:1:14 | C | T |
+| client.ts:13:47:13:47 | C | tslib.ts:6:16:6:16 | C | T |
 | client.ts:14:3:14:3 | x | client.ts:13:22:13:22 | x | V |
-| client.ts:14:5:14:5 | m | client.ts:4:3:4:8 | m() {} | M |
+| client.ts:14:5:14:5 | m | client.ts:4:3:4:3 | m | M |
 | client.ts:15:3:15:3 | y | client.ts:13:28:13:28 | y | V |
-| client.ts:15:5:15:5 | m | tslib.ts:2:3:2:8 | m() {} | M |
+| client.ts:15:5:15:5 | m | tslib.ts:2:3:2:3 | m | M |
 | client.ts:16:3:16:3 | z | client.ts:13:38:13:38 | z | V |
-| client.ts:16:5:16:5 | m | tslib.ts:7:5:7:10 | m() {} | M |
+| client.ts:16:5:16:5 | m | tslib.ts:7:5:7:5 | m | M |
 | d.js:1:17:1:21 | './c' | c.js:1:1:1:20 | <toplevel> | I |
 | d.js:10:1:10:1 | A | d.js:7:1:9:1 | functio ... = 42;\\n} | V |
-| d.js:16:19:16:23 | Super | d.js:12:1:14:1 | class S ... () {}\\n} | V |
+| d.js:16:19:16:23 | Super | d.js:12:7:12:11 | Super | V |
 | d.js:16:25:16:24 | args | d.js:16:25:16:24 | args | V |
 | d.js:20:1:20:1 | o | d.js:3:9:5:1 | {\\n  f:  ... () {}\\n} | V |
 | d.js:20:3:20:3 | f | d.js:4:3:4:18 | f: function() {} | M |
@@ -26,11 +26,11 @@
 | d.js:23:3:23:3 | x | d.js:8:3:8:8 | this.x | M |
 | d.js:24:1:24:1 | a | d.js:22:5:22:5 | a | V |
 | d.js:24:3:24:3 | g | d.js:10:1:10:13 | A.prototype.g | M |
-| d.js:26:13:26:15 | Sub | d.js:16:1:18:1 | class S ... () {}\\n} | M |
+| d.js:26:13:26:15 | Sub | d.js:16:7:16:9 | Sub | M |
 | d.js:27:1:27:1 | x | d.js:26:5:26:5 | x | V |
 | d.js:27:3:27:3 | m | d.js:13:3:13:3 | m | M |
 | d.js:28:1:28:1 | x | d.js:26:5:26:5 | x | V |
 | d.js:28:3:28:3 | n | d.js:17:3:17:3 | n | M |
 | tst.js:1:19:1:23 | './m' | m.js:1:1:2:0 | <toplevel> | I |
-| tst.js:3:5:3:5 | A | m.js:1:8:1:17 | class A {} | M |
+| tst.js:3:5:3:5 | A | m.js:1:14:1:14 | A | M |
 | tst.js:5:15:5:19 | './m' | m.js:1:1:2:0 | <toplevel> | I |