Merge pull request #13 from go-task/feature/os-specific

Feature/os specific

README.md

@@ -42,8 +42,8 @@ task assets build
 If Bash is available (Linux and Windows while on Git Bash), the commands will
 run in Bash, otherwise will fallback to `cmd` (on Windows).
 
-### Environment
 
+### Environment
 You can specify environment variables that are added when running a command:
 
 ```yml
@@ -54,6 +54,30 @@ build:
     hallo: welt
 ```
 
+### OS specific task support
+
+If you add a `Taskfile_{{GOOS}}` you can override or amend your taskfile based on the op;erating system.
+
+Example:
+
+Taskfile.yml:
+
+```yml
+build:
+  cmds:
+  - echo  "default"
+```
+
+Taskfile_linux.yml:
+
+```yml
+build:
+  cmds:
+  - echo  "linux"
+```
+
+Will print out `linux` and not default
+
 ### Running task in another dir
 
 By default, tasks will be executed in the directory where the Taskfile is

errors.go

@@ -4,8 +4,13 @@ import (
 	"fmt"
 )
 
-// ErrNoTaskFile is returned when the program can not find a proper TaskFile
-var ErrNoTaskFile = fmt.Errorf(`task: No task file found (is it named "%s"?)`, TaskFilePath)
+type taskFileNotFound struct {
+	taskFile string
+}
+
+func (err taskFileNotFound) Error() string {
+	return fmt.Sprintf(`task: No task file found (is it named "%s"?)`, err.taskFile)
+}
 
 type taskNotFoundError struct {
 	taskName string

read_taskfile.go

@@ -0,0 +1,58 @@
+package task
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"os"
+
+	"runtime"
+
+	"github.com/BurntSushi/toml"
+	"github.com/imdario/mergo"
+	"gopkg.in/yaml.v2"
+)
+
+func readTaskfile() (map[string]*Task, error) {
+	initialTasks, err := readTaskfileData(TaskFilePath)
+	if err != nil {
+		return nil, err
+	}
+	mergeTasks, err := readTaskfileData(fmt.Sprintf("%s_%s", TaskFilePath, runtime.GOOS))
+	if err != nil {
+		switch err.(type) {
+		default:
+			return nil, err
+		case taskFileNotFound:
+			return initialTasks, nil
+		}
+	}
+	if err := mergo.MapWithOverwrite(&initialTasks, mergeTasks); err != nil {
+		return nil, err
+	}
+	return initialTasks, nil
+}
+
+func readTaskfileData(path string) (tasks map[string]*Task, err error) {
+	if b, err := ioutil.ReadFile(path + ".yml"); err == nil {
+		return tasks, yaml.Unmarshal(b, &tasks)
+	}
+	if b, err := ioutil.ReadFile(path + ".json"); err == nil {
+		return tasks, json.Unmarshal(b, &tasks)
+	}
+	if b, err := ioutil.ReadFile(path + ".toml"); err == nil {
+		return tasks, toml.Unmarshal(b, &tasks)
+	}
+	return nil, taskFileNotFound{path}
+}
+
+func exists(path string) (bool, error) {
+	_, err := os.Stat(path)
+	if err == nil {
+		return true, nil
+	}
+	if os.IsNotExist(err) {
+		return false, nil
+	}
+	return true, err
+}

task.go

@@ -1,17 +1,13 @@
 package task
 
 import (
-	"encoding/json"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
 	"strings"
 
-	"github.com/BurntSushi/toml"
 	"github.com/spf13/pflag"
-	"gopkg.in/yaml.v2"
 )
 
 var (
@@ -185,16 +181,3 @@ func (t *Task) runCommand(i int, envVariables map[string]string) error {
 	}
 	return nil
 }
-
-func readTaskfile() (tasks map[string]*Task, err error) {
-	if b, err := ioutil.ReadFile(TaskFilePath + ".yml"); err == nil {
-		return tasks, yaml.Unmarshal(b, &tasks)
-	}
-	if b, err := ioutil.ReadFile(TaskFilePath + ".json"); err == nil {
-		return tasks, json.Unmarshal(b, &tasks)
-	}
-	if b, err := ioutil.ReadFile(TaskFilePath + ".toml"); err == nil {
-		return tasks, toml.Unmarshal(b, &tasks)
-	}
-	return nil, ErrNoTaskFile
-}