Improved handling of numeric keys

When there is no match at a given path, numeric keys are assumed to be strings.
To create an array '+' must be used.

e.g: yq n thing[+].cat fred
will create an array under thing, whereas
yq n thing[0].cat fred
will create a map under thing, with a key '0'

commands_test.go

@@ -385,12 +385,11 @@ func TestPrefixCmdArray(t *testing.T) {
 	defer removeTempYamlFile(filename)
 
 	cmd := getRootCommand()
-	result := runCmd(cmd, fmt.Sprintf("prefix %s [0].d.[1]", filename))
+	result := runCmd(cmd, fmt.Sprintf("prefix %s [+].d.[+]", filename))
 	if result.Error != nil {
 		t.Error(result.Error)
 	}
 	expectedOutput := `- d:
-  - null
   - b:
       c: 3
 `

data_navigator.go

@@ -89,14 +89,15 @@ func updatedChildValue(child interface{}, remainingPaths []string, value interfa
 	}
 	log.Debugf("updatedChildValue for child %v with path %v to set value %v", child, remainingPaths, value)
 	log.Debugf("type of child is %v", reflect.TypeOf(child))
-	_, nextIndexErr := strconv.ParseInt(remainingPaths[0], 10, 64)
+
-	arrayCommand := nextIndexErr == nil || remainingPaths[0] == "+" || remainingPaths[0] == "*"
 	switch child := child.(type) {
 	case nil:
-		if arrayCommand {
+		if remainingPaths[0] == "+" || remainingPaths[0] == "*" {
 			return writeArray(child, remainingPaths, value)
 		}
 	case []interface{}:
+		_, nextIndexErr := strconv.ParseInt(remainingPaths[0], 10, 64)
+		arrayCommand := nextIndexErr == nil || remainingPaths[0] == "+" || remainingPaths[0] == "*"
 		if arrayCommand {
 			return writeArray(child, remainingPaths, value)
 		}

data_navigator_test.go

@@ -260,7 +260,7 @@ a: apple
 b:
 - c: "4"`
 
-	updated := writeMap(data, []string{"b", "0", "c"}, "4")
+	updated := writeMap(data, []string{"b", "+", "c"}, "4")
 	got, _ := yamlToString(updated)
 	assertResult(t, expected, got)
 }
@@ -275,7 +275,7 @@ b:
   d:
   - "4"`
 
-	updated := writeMap(data, []string{"b", "d", "0"}, "4")
+	updated := writeMap(data, []string{"b", "d", "+"}, "4")
 	got, _ := yamlToString(updated)
 	assertResult(t, expected, got)
 }

examples/instruction_sample.yaml

@@ -1,2 +1,2 @@
 b.c: cat
-b.e[0].name: Mike Farah
+b.e[+].name: Mike Farah