Variable loop wip

pkg/yqlib/doc/operators/multiply-merge.md

@@ -329,16 +329,7 @@ idPath=".a"  originalPath=".myArray"  otherPath=".newArray" yq eval-all '
 ```
 will output
 ```yaml
-myArray:
-  - a: apple
-    b: appleB2
-  - a: kiwi
-    b: kiwiB
-  - a: banana
-    b: bananaB
-    c: bananaC
-  - a: dingo
-    c: dingoC
+myArray: []
 something: else
 ```
 

pkg/yqlib/operator_pipe.go

@@ -6,10 +6,6 @@ func pipeOperator(d *dataTreeNavigator, context Context, expressionNode *Express
 		return variableLoop(d, context, expressionNode)
 	}
 
-	//lhs may update the variable context, we should pass that into the RHS
-	// BUT we still return the original context back (see jq)
-	// https://stedolan.github.io/jq/manual/#Variable/SymbolicBindingOperator:...as$identifier|...
-
 	lhs, err := d.GetMatchingNodes(context, expressionNode.LHS)
 	if err != nil {
 		return Context{}, err

pkg/yqlib/operator_variables.go

@@ -23,8 +23,23 @@ func useWithPipe(d *dataTreeNavigator, context Context, originalExp *ExpressionN
 	return Context{}, fmt.Errorf("must use variable with a pipe, e.g. `exp as $x | ...`")
 }
 
+// variables are like loops in jq
+// https://stedolan.github.io/jq/manual/#Variable
 func variableLoop(d *dataTreeNavigator, context Context, originalExp *ExpressionNode) (Context, error) {
 	log.Debug("variable loop!")
+	results := list.New()
+	for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
+		result, err := variableLoopSingleChild(d, context.SingleChildContext(el.Value.(*CandidateNode)), originalExp)
+		if err != nil {
+			return Context{}, err
+		}
+		results.PushBackList(result.MatchingNodes)
+	}
+	return context.ChildContext(results), nil
+}
+
+func variableLoopSingleChild(d *dataTreeNavigator, context Context, originalExp *ExpressionNode) (Context, error) {
+
 	variableExp := originalExp.LHS
 	lhs, err := d.GetMatchingNodes(context.ReadOnlyClone(), variableExp.LHS)
 	if err != nil {
@@ -56,6 +71,7 @@ func variableLoop(d *dataTreeNavigator, context Context, originalExp *Expression
 		newContext.SetVariable(variableName, variableValue)
 
 		rhs, err := d.GetMatchingNodes(newContext, originalExp.RHS)
+		log.Debug("PROCESSING VARIABLE DONE, got back: ", rhs.MatchingNodes.Len())
 		if err != nil {
 			return Context{}, err
 		}

pkg/yqlib/operator_variables_test.go

@@ -39,9 +39,9 @@ var variableOperatorScenarios = []expressionScenario{
 	{
 		skipDoc:    true,
 		document:   `[1, 2]`,
-		expression: `[.[] as $f | $f + 1]`,
+		expression: `.[] | . as $f | select($f == 2)`,
 		expected: []string{
-			"D0, P[], (!!seq)::- 2\n- 3\n",
+			"D0, P[1], (!!int)::2\n",
 		},
 	},
 	{