Better stacktrace for manifestation, +: and object assertions.

Fixes #282

internal/program/desugarer.go

@@ -62,7 +62,12 @@ func desugarFields(nodeBase ast.NodeBase, fields *ast.ObjectFields, objLevel int
 			if msg == nil {
 				msg = buildLiteralString("Object assertion failed.")
 			}
-			onFailure := &ast.Error{Expr: msg}
+			onFailure := &ast.Error{
+				NodeBase: ast.NodeBase{
+					LocRange: field.LocRange,
+				},
+				Expr: msg,
+			}
 			asserts = append(asserts, &ast.Conditional{
 				NodeBase: ast.NodeBase{
 					LocRange: field.LocRange,

interpreter.go

@@ -35,9 +35,9 @@ type environment struct {
 
 	// Bindings introduced in this frame. The way previous bindings are treated
 	// depends on the type of a frame.
-	// If isCall == true then previous bindings are ignored (it's a clean
+	// If cleanEnv == true then previous bindings are ignored (it's a clean
 	// environment with just the variables we have here).
-	// If isCall == false then if this frame doesn't contain a binding
+	// If cleanEnv == false then if this frame doesn't contain a binding
 	// previous bindings will be used.
 	upValues bindingFrame
 }
@@ -52,7 +52,7 @@ func makeEnvironment(upValues bindingFrame, sb selfBinding) environment {
 func (i *interpreter) getCurrentStackTrace() []traceFrame {
 	var result []traceFrame
 	for _, f := range i.stack.stack {
-		if f.isCall {
+		if f.cleanEnv {
 			result = append(result, traceElementToTraceFrame(f.trace))
 		}
 	}
@@ -65,8 +65,7 @@ func (i *interpreter) getCurrentStackTrace() []traceFrame {
 type callFrame struct {
 	// True if it switches to a clean environment (function call or array element)
 	// False otherwise, e.g. for local
-	// This makes callFrame a misnomer as it is technically not always a call...
-	isCall bool
+	cleanEnv bool
 
 	// Tracing information about the place where it was called from.
 	trace traceElement
@@ -87,8 +86,8 @@ func dumpCallFrame(c *callFrame) string {
 	} else {
 		loc = *c.trace.loc
 	}
-	return fmt.Sprintf("<callFrame isCall = %t location = %v trimmable = %t>",
-		c.isCall,
+	return fmt.Sprintf("<callFrame cleanEnv = %t location = %v trimmable = %t>",
+		c.cleanEnv,
 		loc,
 		c.trimmable,
 	)
@@ -121,7 +120,7 @@ func (s *callStack) top() *callFrame {
 // of the frame we want to pop.
 func (s *callStack) popIfExists(whichFrame int) {
 	if len(s.stack) == whichFrame {
-		if s.top().isCall {
+		if s.top().cleanEnv {
 			s.calls--
 		}
 		s.setCurrentTrace(s.stack[len(s.stack)-1].trace)
@@ -132,7 +131,7 @@ func (s *callStack) popIfExists(whichFrame int) {
 /** If there is a trimmable frame followed by some locals, pop them all. */
 func (s *callStack) tailCallTrimStack() {
 	for i := len(s.stack) - 1; i >= 0; i-- {
-		if s.stack[i].isCall {
+		if s.stack[i].cleanEnv {
 			if !s.stack[i].trimmable {
 				return
 			}
@@ -167,7 +166,7 @@ func (s *callStack) newCall(env environment, trimmable bool) {
 		panic("Saving empty traceElement on stack")
 	}
 	s.stack = append(s.stack, &callFrame{
-		isCall:    true,
+		cleanEnv:  true,
 		trace:     s.currentTrace,
 		env:       env,
 		trimmable: trimmable,
@@ -187,7 +186,7 @@ func (s *callStack) newLocal(vars bindingFrame) {
 // getSelfBinding resolves the self construct
 func (s *callStack) getSelfBinding() selfBinding {
 	for i := len(s.stack) - 1; i >= 0; i-- {
-		if s.stack[i].isCall {
+		if s.stack[i].cleanEnv {
 			return s.stack[i].env.selfBinding
 		}
 	}
@@ -201,7 +200,7 @@ func (s *callStack) lookUpVar(id ast.Identifier) *cachedThunk {
 		if present {
 			return bind
 		}
-		if s.stack[i].isCall {
+		if s.stack[i].cleanEnv {
 			// Nothing beyond the captured environment of the thunk / closure.
 			break
 		}
@@ -654,6 +653,15 @@ func (i *interpreter) manifestJSON(v value) (interface{}, error) {
 	if i.stack.currentTrace == (traceElement{}) {
 		panic("manifesting JSON with empty traceElement")
 	}
+
+	// Fresh frame for better stack traces
+	err := i.newCall(environment{}, false)
+	if err != nil {
+		return nil, err
+	}
+	stackSize := len(i.stack.stack)
+	defer i.stack.popIfExists(stackSize)
+
 	switch v := v.(type) {
 
 	case *valueBoolean:
@@ -673,16 +681,23 @@ func (i *interpreter) manifestJSON(v value) (interface{}, error) {
 
 	case *valueArray:
 		result := make([]interface{}, 0, len(v.elements))
-		for _, th := range v.elements {
+		for index, th := range v.elements {
+			msg := ast.MakeLocationRangeMessage(fmt.Sprintf("Array element %d", index))
+			i.stack.setCurrentTrace(traceElement{
+				loc: &msg,
+			})
 			elVal, err := i.evaluatePV(th)
 			if err != nil {
+				i.stack.clearCurrentTrace()
 				return nil, err
 			}
 			elem, err := i.manifestJSON(elVal)
 			if err != nil {
+				i.stack.clearCurrentTrace()
 				return nil, err
 			}
 			result = append(result, elem)
+			i.stack.clearCurrentTrace()
 		}
 		return result, nil
 
@@ -690,24 +705,37 @@ func (i *interpreter) manifestJSON(v value) (interface{}, error) {
 		fieldNames := objectFields(v, withoutHidden)
 		sort.Strings(fieldNames)
 
+		msg := ast.MakeLocationRangeMessage("Checking object assertions")
+		i.stack.setCurrentTrace(traceElement{
+			loc: &msg,
+		})
 		err := checkAssertions(i, v)
 		if err != nil {
+			i.stack.clearCurrentTrace()
 			return nil, err
 		}
+		i.stack.clearCurrentTrace()
 
 		result := make(map[string]interface{})
 
 		for _, fieldName := range fieldNames {
+			msg := ast.MakeLocationRangeMessage(fmt.Sprintf("Field %#v", fieldName))
+			i.stack.setCurrentTrace(traceElement{
+				loc: &msg,
+			})
 			fieldVal, err := v.index(i, fieldName)
 			if err != nil {
+				i.stack.clearCurrentTrace()
 				return nil, err
 			}
 
 			field, err := i.manifestJSON(fieldVal)
 			if err != nil {
+				i.stack.clearCurrentTrace()
 				return nil, err
 			}
 			result[fieldName] = field
+			i.stack.clearCurrentTrace()
 		}
 
 		return result, nil
@@ -944,10 +972,13 @@ func (i *interpreter) EvalInCleanEnv(env *environment, ast ast.Node, trimmable b
 	stackSize := len(i.stack.stack)
 
 	val, err := i.evaluate(ast, tailCall)
+	if err != nil {
+		return nil, err
+	}
 
 	i.stack.popIfExists(stackSize)
 
-	return val, err
+	return val, nil
 }
 
 func (i *interpreter) evaluatePV(ph potentialValue) (value, error) {
@@ -1211,7 +1242,14 @@ func makeInitialEnv(filename string, baseStd *valueObject) environment {
 	)
 }
 
-func evaluateAux(i *interpreter, node ast.Node, tla vmExtMap) (value, traceElement, error) {
+func manifestationTrace() traceElement {
+	manifestationLoc := ast.MakeLocationRangeMessage("During manifestation")
+	return traceElement{
+		loc: &manifestationLoc,
+	}
+}
+
+func evaluateAux(i *interpreter, node ast.Node, tla vmExtMap) (value, error) {
 	evalLoc := ast.MakeLocationRangeMessage("During evaluation")
 	evalTrace := traceElement{
 		loc: &evalLoc,
@@ -1221,7 +1259,7 @@ func evaluateAux(i *interpreter, node ast.Node, tla vmExtMap) (value, traceEleme
 	result, err := i.EvalInCleanEnv(&env, node, false)
 	i.stack.clearCurrentTrace()
 	if err != nil {
-		return nil, traceElement{}, err
+		return nil, err
 	}
 	// If it's not a function, ignore TLA
 	if f, ok := result.(*valueFunction); ok {
@@ -1238,14 +1276,10 @@ func evaluateAux(i *interpreter, node ast.Node, tla vmExtMap) (value, traceEleme
 		result, err = f.call(i, args)
 		i.stack.clearCurrentTrace()
 		if err != nil {
-			return nil, traceElement{}, err
+			return nil, err
 		}
 	}
-	manifestationLoc := ast.MakeLocationRangeMessage("During manifestation")
-	manifestationTrace := traceElement{
-		loc: &manifestationLoc,
-	}
-	return result, manifestationTrace, nil
+	return result, nil
 }
 
 // TODO(sbarzowski) this function takes far too many arguments - build interpreter in vm instead
@@ -1257,13 +1291,13 @@ func evaluate(node ast.Node, ext vmExtMap, tla vmExtMap, nativeFuncs map[string]
 		return "", err
 	}
 
-	result, manifestationTrace, err := evaluateAux(i, node, tla)
+	result, err := evaluateAux(i, node, tla)
 	if err != nil {
 		return "", err
 	}
 
 	var buf bytes.Buffer
-	i.stack.setCurrentTrace(manifestationTrace)
+	i.stack.setCurrentTrace(manifestationTrace())
 	if stringOutputMode {
 		err = i.manifestString(&buf, result)
 	} else {
@@ -1286,12 +1320,12 @@ func evaluateMulti(node ast.Node, ext vmExtMap, tla vmExtMap, nativeFuncs map[st
 		return nil, err
 	}
 
-	result, manifestationTrace, err := evaluateAux(i, node, tla)
+	result, err := evaluateAux(i, node, tla)
 	if err != nil {
 		return nil, err
 	}
 
-	i.stack.setCurrentTrace(manifestationTrace)
+	i.stack.setCurrentTrace(manifestationTrace())
 	manifested, err := i.manifestAndSerializeMulti(result, stringOutputMode)
 	i.stack.clearCurrentTrace()
 	return manifested, err
@@ -1306,12 +1340,12 @@ func evaluateStream(node ast.Node, ext vmExtMap, tla vmExtMap, nativeFuncs map[s
 		return nil, err
 	}
 
-	result, manifestationTrace, err := evaluateAux(i, node, tla)
+	result, err := evaluateAux(i, node, tla)
 	if err != nil {
 		return nil, err
 	}
 
-	i.stack.setCurrentTrace(manifestationTrace)
+	i.stack.setCurrentTrace(manifestationTrace())
 	manifested, err := i.manifestAndSerializeYAMLStream(result)
 	i.stack.clearCurrentTrace()
 	return manifested, err

linter/internal/types/stdlib.go

@@ -124,7 +124,7 @@ func prepareStdlib(g *typeGraph) {
 		"setInter":  g.newFuncType(anyArrayType, []ast.Parameter{required("a"), required("b"), optional("keyF")}),
 		"setUnion":  g.newFuncType(anyArrayType, []ast.Parameter{required("a"), required("b"), optional("keyF")}),
 		"setDiff":   g.newFuncType(anyArrayType, []ast.Parameter{required("a"), required("b"), optional("keyF")}),
-		"setMember": g.newFuncType(anyArrayType, []ast.Parameter{required("x"), required("arr"), optional("keyF")}),
+		"setMember": g.newFuncType(boolType, []ast.Parameter{required("x"), required("arr"), optional("keyF")}),
 
 		// Encoding
 

linter/testdata/stdlib_return_types.jsonnet

@@ -0,0 +1 @@
+!std.setMember([1, 2, 3], 1)

testdata/error_in_object_local.golden

@@ -9,6 +9,9 @@ RUNTIME ERROR: xxx
 
 { local foo(bar) = error bar, baz: foo("xxx") }
 
+-------------------------------------------------
+	Field "baz"	
+
 -------------------------------------------------
 	During manifestation	
 

testdata/function_manifested.golden

@@ -1,4 +1,7 @@
 RUNTIME ERROR: couldn't manifest function as JSON
+-------------------------------------------------
+	Field "f"	
+
 -------------------------------------------------
 	During manifestation	
 

testdata/missing_super.golden

@@ -4,6 +4,9 @@ RUNTIME ERROR: Attempt to use super when there is no super class.
 
 { x: super.x }
 
+-------------------------------------------------
+	Field "x"	
+
 -------------------------------------------------
 	During manifestation	
 

testdata/object_comp_err_elem.golden

@@ -4,6 +4,9 @@ RUNTIME ERROR: xxx
 
 { ["x"]:  error "xxx" for x in [1] }
 
+-------------------------------------------------
+	Field "x"	
+
 -------------------------------------------------
 	During manifestation	
 

testdata/object_invariant10.golden

@@ -1,6 +1,11 @@
 RUNTIME ERROR: Object assertion failed.
 -------------------------------------------------
+	testdata/object_invariant10:1:16-28	
 
+{ assert true, assert false }
+
+-------------------------------------------------
+	Checking object assertions	
 
 -------------------------------------------------
 	During manifestation	

testdata/object_invariant11.golden

@@ -1,6 +1,8 @@
 RUNTIME ERROR: Object assertion failed.
 -------------------------------------------------
+	testdata/object_invariant11:1:3-15	
 
+{ assert false }.x
 
 -------------------------------------------------
 	testdata/object_invariant11:1:1-19	$

testdata/object_invariant13.golden

@@ -4,6 +4,9 @@ RUNTIME ERROR: x
 
 { assert error "x" }
 
+-------------------------------------------------
+	Checking object assertions	
+
 -------------------------------------------------
 	During manifestation	
 

testdata/object_invariant14.golden

@@ -1,6 +1,11 @@
 RUNTIME ERROR: xxx
 -------------------------------------------------
+	testdata/object_invariant14:1:3-22	
 
+{ assert false: "xxx" }
+
+-------------------------------------------------
+	Checking object assertions	
 
 -------------------------------------------------
 	During manifestation	

testdata/object_invariant2.golden

@@ -1,6 +1,11 @@
 RUNTIME ERROR: Object assertion failed.
 -------------------------------------------------
+	testdata/object_invariant2:1:3-15	
 
+{ assert false }
+
+-------------------------------------------------
+	Checking object assertions	
 
 -------------------------------------------------
 	During manifestation	

testdata/object_invariant7.golden

@@ -4,6 +4,9 @@ RUNTIME ERROR: Attempt to use super when there is no super class.
 
 { x: 5, assert super.x == 5 } 
 
+-------------------------------------------------
+	Checking object assertions	
+
 -------------------------------------------------
 	During manifestation	
 

testdata/object_invariant8.golden

@@ -1,6 +1,11 @@
 RUNTIME ERROR: Object assertion failed.
 -------------------------------------------------
+	testdata/object_invariant8:1:9-27	
 
+{ x: 5, assert self.x == 4 }
+
+-------------------------------------------------
+	Checking object assertions	
 
 -------------------------------------------------
 	During manifestation	

testdata/object_invariant9.golden

@@ -1,6 +1,11 @@
 RUNTIME ERROR: Object assertion failed.
 -------------------------------------------------
+	testdata/object_invariant9:1:16-28	
 
+{ assert true, assert false } 
+
+-------------------------------------------------
+	Checking object assertions	
 
 -------------------------------------------------
 	During manifestation	

testdata/object_invariant_plus.golden

@@ -1,6 +1,11 @@
 RUNTIME ERROR: Object assertion failed.
 -------------------------------------------------
+	testdata/object_invariant_plus:1:2-14	
 
+{assert false} + {assert true}
+
+-------------------------------------------------
+	Checking object assertions	
 
 -------------------------------------------------
 	During manifestation	

testdata/object_invariant_plus2.golden

@@ -1,6 +1,11 @@
 RUNTIME ERROR: Object assertion failed.
 -------------------------------------------------
+	testdata/object_invariant_plus2:1:18-30	
 
+{assert true} + {assert false}
+
+-------------------------------------------------
+	Checking object assertions	
 
 -------------------------------------------------
 	During manifestation	

testdata/object_invariant_plus6.golden

@@ -1,6 +1,11 @@
 RUNTIME ERROR: yyy
 -------------------------------------------------
+	testdata/object_invariant_plus6:1:27-46	
 
+{ assert false: "xxx" } { assert false: "yyy" }
+
+-------------------------------------------------
+	Checking object assertions	
 
 -------------------------------------------------
 	During manifestation	

testdata/stacktrace_assert.golden

@@ -0,0 +1,13 @@
+RUNTIME ERROR: Object assertion failed.
+-------------------------------------------------
+	testdata/stacktrace_assert:1:3-15	
+
+{ assert false }
+
+-------------------------------------------------
+	Checking object assertions	
+
+-------------------------------------------------
+	During manifestation	
+
+

testdata/stacktrace_assert.jsonnet

@@ -0,0 +1 @@
+{ assert false }

testdata/stacktrace_plussuper.golden

@@ -0,0 +1,13 @@
+RUNTIME ERROR: Unexpected type null
+-------------------------------------------------
+	testdata/stacktrace_plussuper:2:7-9	+:
+
+  a+: {},
+
+-------------------------------------------------
+	Field "a"	
+
+-------------------------------------------------
+	During manifestation	
+
+

testdata/stacktrace_plussuper.jsonnet

@@ -0,0 +1,5 @@
+local a(input) = input + {
+  a+: {},
+};
+
+a({a: null})

testdata/supersugar8.golden

@@ -1,6 +1,11 @@
 RUNTIME ERROR: Object assertion failed.
 -------------------------------------------------
+	testdata/supersugar8:1:3-16	
 
+{ assert self.x } { x +: false }
+
+-------------------------------------------------
+	Checking object assertions	
 
 -------------------------------------------------
 	During manifestation	

thunks.go

@@ -36,6 +36,10 @@ func (rv *readyValue) evaluate(i *interpreter, sb selfBinding, origBinding bindi
 	return rv.content, nil
 }
 
+func (rv *readyValue) loc() *ast.LocationRange {
+	return &ast.LocationRange{}
+}
+
 // potentialValues
 // -------------------------------------
 
@@ -89,7 +93,12 @@ type codeUnboundField struct {
 
 func (f *codeUnboundField) evaluate(i *interpreter, sb selfBinding, origBindings bindingFrame, fieldName string) (value, error) {
 	env := makeEnvironment(origBindings, sb)
-	return i.EvalInCleanEnv(&env, f.body, false)
+	val, err := i.EvalInCleanEnv(&env, f.body, false)
+	return val, err
+}
+
+func (f *codeUnboundField) loc() *ast.LocationRange {
+	return f.body.Loc()
 }
 
 // Provide additional bindings for a field. It shadows bindings from the object.
@@ -110,24 +119,54 @@ func (f *bindingsUnboundField) evaluate(i *interpreter, sb selfBinding, origBind
 	return f.inner.evaluate(i, sb, upValues, fieldName)
 }
 
+func (f *bindingsUnboundField) loc() *ast.LocationRange {
+	return f.inner.loc()
+}
+
 // plusSuperUnboundField represents a `field+: ...` that hasn't been bound to an object.
 type plusSuperUnboundField struct {
 	inner unboundField
 }
 
 func (f *plusSuperUnboundField) evaluate(i *interpreter, sb selfBinding, origBinding bindingFrame, fieldName string) (value, error) {
+	err := i.newCall(environment{}, false)
+	if err != nil {
+		return nil, err
+	}
+	stackSize := len(i.stack.stack)
+	defer i.stack.popIfExists(stackSize)
+
+	context := "+:"
+	i.stack.setCurrentTrace(traceElement{
+		loc:     f.loc(),
+		context: &context,
+	})
+	defer i.stack.clearCurrentTrace()
+
 	right, err := f.inner.evaluate(i, sb, origBinding, fieldName)
 	if err != nil {
 		return nil, err
 	}
+
 	if !objectHasField(sb.super(), fieldName, withHidden) {
 		return right, nil
 	}
+
 	left, err := objectIndex(i, sb.super(), fieldName)
 	if err != nil {
 		return nil, err
 	}
-	return builtinPlus(i, left, right)
+
+	value, err := builtinPlus(i, left, right)
+	if err != nil {
+		return nil, err
+	}
+
+	return value, nil
+}
+
+func (f *plusSuperUnboundField) loc() *ast.LocationRange {
+	return f.inner.loc()
 }
 
 // evalCallables

value.go

@@ -572,6 +572,7 @@ func checkAssertionsHelper(i *interpreter, obj *valueObject, curr uncachedObject
 	default:
 		panic(fmt.Sprintf("Unknown object type %#v", curr))
 	}
+
 }
 
 func checkAssertions(i *interpreter, obj *valueObject) error {
@@ -611,6 +612,7 @@ type simpleObjectField struct {
 // unboundField is a field that doesn't know yet in which object it is.
 type unboundField interface {
 	evaluate(i *interpreter, sb selfBinding, origBinding bindingFrame, fieldName string) (value, error)
+	loc() *ast.LocationRange
 }
 
 // extendedObject represents an object created through inheritance (left + right).