Support $ in comprehesions, fixes #68

desugarer.go

@@ -228,6 +228,11 @@ func desugarArrayComp(comp *ast.ArrayComp, objLevel int) (ast.Node, error) {
 
 func desugarObjectComp(comp *ast.ObjectComp, objLevel int) (ast.Node, error) {
 
+	if objLevel == 0 {
+		dollar := ast.Identifier("$")
+		comp.Fields = append(comp.Fields, ast.ObjectFieldLocalNoMethod(&dollar, &ast.Self{}))
+	}
+
 	// TODO(sbarzowski) find a consistent convention to prevent desugaring the same thing twice
 	// here we deeply desugar fields and it will happen again
 	err := desugarFields(*comp.Loc(), &comp.Fields, objLevel+1)

testdata/object_comp_dollar.golden

@@ -0,0 +1,5 @@
+{
+   "a": 42,
+   "b": 43,
+   "c": 43
+}

testdata/object_comp_dollar.jsonnet

@@ -0,0 +1 @@
+{ [x]: if x == "a" then 42 else $.a + 1 for x in ["a", "b", "c"] }

testdata/object_comp_dollar2.golden

@@ -0,0 +1,14 @@
+{
+   "a": {
+      "a": 1,
+      "b": 42
+   },
+   "b": {
+      "a": 1,
+      "b": 43
+   },
+   "c": {
+      "a": 1,
+      "b": 43
+   }
+}

testdata/object_comp_dollar2.jsonnet

@@ -0,0 +1 @@
+{ [x]: { a: 1, b: if x == "a" then 42 else $.a.b + 1 } for x in ["a", "b", "c"] }

testdata/object_comp_dollar3.golden

@@ -0,0 +1,7 @@
+{
+   "obj": {
+      "a": 1,
+      "b": 2,
+      "c": 2
+   }
+}

testdata/object_comp_dollar3.jsonnet

@@ -0,0 +1,3 @@
+local obj = { [x]: if x == "a" then 42 else $.a + 1 for x in ["a", "b", "c"] };
+{ obj: obj + {a: 1} }
+