Add merge command

3 files changed, 41 insertions, 0 deletions

diff --git a/main/command.go b/main/command.go
index 3f22821..6d75974 100644
--- a/main/command.go
+++ b/main/command.go
@@ -44,13 +44,47 @@ func (cmd AppendNextCommand) exec(state *ProgramState) {
 	if err != nil {
 		panic("Missing next value")
 	}
+
+	state.prevStart = nextItem.PrevStart
+	state.start = nextItem.Start
+	state.end = nextItem.End
+	state.nextEnd = nextItem.NextEnd
+
 	state.value = append(state.value, nextItem.Value)
+
 	state.pc++
 }
 func (cmd AppendNextCommand) String() string {
 	return "N"
 }
 
+type MergeCommand struct {}
+func (cmd MergeCommand) exec(state *ProgramState) {
+	nextItem, err := state.in.Read()
+	if err != nil {
+		panic("Missing next value")
+	}
+
+	state.prevStart = nextItem.PrevStart
+	state.start = nextItem.Start
+	state.end = nextItem.End
+	state.nextEnd = nextItem.NextEnd
+
+	if len(state.value) == 0 {
+		state.value = []walk.Value {nextItem.Value}
+	} else {
+		state.value = append(
+			state.value[:len(state.value) - 1],
+			walk.Merge(state.value[len(state.value) - 1], nextItem.Value)...
+		)
+	}
+
+	state.pc++
+}
+func (cmd MergeCommand) String() string {
+	return "m"
+}
+
 type DeleteValueCommand struct {}
 func (cmd DeleteValueCommand) exec(state *ProgramState) {
 	state.value = nil
diff --git a/main/main_test.go b/main/main_test.go
index 7aa90aa..74f179b 100644
--- a/main/main_test.go
+++ b/main/main_test.go
@@ -64,6 +64,11 @@ func TestMain(t *testing.T) {
 			input: miscInput,
 			expected: `["Charlie Johnson","Tom Johnson","Charlie Chaplin","John Johnson"]`,
 		},
+		{
+			program: "s/#(\"people\" @(. #(\"first_name\" .)#)@)#/{ ms/#(\"people\" @(. (#(\"first_name\" \".{-0}$a\" \"last_name\" \".{-0}$b\")#$_) `#(\"name\" \"$a $b\")#`)@)#/ }",
+			input: miscInput,
+			expected: `{"something":{"nested":"Here is my test value"},"array":["Hello","world","these","are","values"],"people":[{"name":"Charlie Johnson","age":22},{"name":"Tom Johnson","age":18},{"name":"Charlie Chaplin","age":122},{"name":"John Johnson","age":48}]}`,
+		},
 	}
 
 	for i, test := range tests {
diff --git a/main/parse.go b/main/parse.go
index 3e0e80b..3c24e6c 100644
--- a/main/parse.go
+++ b/main/parse.go
@@ -69,6 +69,8 @@ func (p *parser) parseBasicCommand(commands []Command, commandChar rune) []Comma
 			return append(commands, NextCommand{})
 		case 'N':
 			return append(commands, AppendNextCommand{})
+		case 'm':
+			return append(commands, MergeCommand{})
 		case 's':
 			ast := p.parseSubex()
 			subex := subex.CompileTransducer(ast)