Bugfix: Read yaml array

Parsing an array into MapSlice results in `[{nil, nil}]`.
Parse into `[]map[interface{}]interface{}` allows for the processing of
top level arrays in the document.

Resolves: #23

commands_test.go

@@ -106,6 +106,99 @@ func TestReadCmd(t *testing.T) {
 	assertResult(t, "2\n", result.Output)
 }
 
+func TestReadCmd_ArrayYaml(t *testing.T) {
+	cmd := getRootCommand()
+	result := runCmd(cmd, "read examples/array.yaml [0].gather_facts")
+	if result.Error != nil {
+		t.Error(result.Error)
+	}
+	assertResult(t, "false\n", result.Output)
+}
+
+func TestReadCmd_ArrayYaml_NoPath(t *testing.T) {
+	cmd := getRootCommand()
+	result := runCmd(cmd, "read examples/array.yaml")
+	if result.Error != nil {
+		t.Error(result.Error)
+	}
+	expectedOutput := `- become: true
+  gather_facts: false
+  hosts: lalaland
+  name: Apply smth
+  roles:
+  - lala
+  - land
+  serial: 1
+`
+	assertResult(t, expectedOutput, result.Output)
+}
+
+func TestReadCmd_ArrayYaml_OneElement(t *testing.T) {
+	cmd := getRootCommand()
+	result := runCmd(cmd, "read examples/array.yaml [0]")
+	if result.Error != nil {
+		t.Error(result.Error)
+	}
+	expectedOutput := `become: true
+gather_facts: false
+hosts: lalaland
+name: Apply smth
+roles:
+- lala
+- land
+serial: 1
+`
+	assertResult(t, expectedOutput, result.Output)
+}
+
+func TestReadCmd_ArrayYaml_Splat(t *testing.T) {
+	cmd := getRootCommand()
+	result := runCmd(cmd, "read examples/array.yaml [*]")
+	if result.Error != nil {
+		t.Error(result.Error)
+	}
+	expectedOutput := `- become: true
+  gather_facts: false
+  hosts: lalaland
+  name: Apply smth
+  roles:
+  - lala
+  - land
+  serial: 1
+`
+	assertResult(t, expectedOutput, result.Output)
+}
+
+func TestReadCmd_ArrayYaml_SplatKey(t *testing.T) {
+	cmd := getRootCommand()
+	result := runCmd(cmd, "read examples/array.yaml [*].gather_facts")
+	if result.Error != nil {
+		t.Error(result.Error)
+	}
+	expectedOutput := "- false\n"
+	assertResult(t, expectedOutput, result.Output)
+}
+
+func TestReadCmd_ArrayYaml_ErrorBadPath(t *testing.T) {
+	cmd := getRootCommand()
+	result := runCmd(cmd, "read examples/array.yaml [x].gather_facts")
+	if result.Error == nil {
+		t.Error("Expected command to fail due to invalid path")
+	}
+	expectedOutput := `Error accessing array: strconv.ParseInt: parsing "x": invalid syntax`
+	assertResult(t, expectedOutput, result.Error.Error())
+}
+
+func TestReadCmd_ArrayYaml_Splat_ErrorBadPath(t *testing.T) {
+	cmd := getRootCommand()
+	result := runCmd(cmd, "read examples/array.yaml [*].roles[x]")
+	if result.Error == nil {
+		t.Error("Expected command to fail due to invalid path")
+	}
+	expectedOutput := `Error accessing array: strconv.ParseInt: parsing "x": invalid syntax`
+	assertResult(t, expectedOutput, result.Error.Error())
+}
+
 func TestReadCmd_Error(t *testing.T) {
 	cmd := getRootCommand()
 	result := runCmd(cmd, "read")

examples/array.yaml

@@ -0,0 +1,9 @@
+---
+- become: true
+  gather_facts: false
+  hosts: lalaland
+  name: "Apply smth"
+  roles:
+    - lala
+    - land
+  serial: 1

yaml.go

@@ -185,6 +185,17 @@ func read(args []string) (interface{}, error) {
 		path = "thing." + path
 	}
 
+	if parsedData != nil && parsedData[0].Key == nil {
+		var interfaceData []map[interface{}]interface{}
+		if err := readData(args[0], &interfaceData); err == nil {
+			var listMap []yaml.MapSlice
+			for _, item := range interfaceData {
+				listMap = append(listMap, mapToMapSlice(item))
+			}
+			return readYamlArray(listMap, path)
+		}
+	}
+
 	if path == "" {
 		return parsedData, nil
 	}
@@ -194,6 +205,38 @@ func read(args []string) (interface{}, error) {
 	return readMap(parsedData, paths[0], paths[1:])
 }
 
+func readYamlArray(listMap []yaml.MapSlice, path string) (interface{}, error) {
+	if path == "" {
+		return listMap, nil
+	}
+
+	var paths = parsePath(path)
+
+	if paths[0] == "*" {
+		if len(paths[1:]) == 0 {
+			return listMap, nil
+		}
+		var results []interface{}
+		for _, m := range listMap {
+			value, err := readMap(m, paths[1], paths[2:])
+			if err != nil {
+				return nil, err
+			}
+			results = append(results, value)
+		}
+		return results, nil
+	}
+
+	index, err := strconv.ParseInt(paths[0], 10, 64)
+	if err != nil {
+		return nil, fmt.Errorf("Error accessing array: %v", err)
+	}
+	if len(paths[1:]) == 0 {
+		return listMap[index], nil
+	}
+	return readMap(listMap[index], paths[1], paths[2:])
+}
+
 func newProperty(cmd *cobra.Command, args []string) error {
 	updatedData, err := newYaml(args)
 	if err != nil {