Allow vars in dotenv paths, including environment variables

Closes #453
Closes #434
Ref #433

Co-authored-by: Andrey Nering <[email protected]>

Author: nfo

docs/usage.md

@@ -78,18 +78,25 @@ setting:
 KEYNAME=VALUE
 ```
 
+```
+# testing/.env
+ENDPOINT=testing.com
+```
 
 ```yaml
 # Taskfile.yml
 
 version: '3'
 
-dotenv: ['.env']
+env:
+  ENV: testing
+
+dotenv: ['.env', '{{.ENV}}/.env.', '{{.HOME}}/.env']
 
 tasks:
   greet:
     cmds:
-      - echo "Using $KEYNAME"
+      - echo "Using $KEYNAME and endpoint $ENDPOINT"
 ```
 
 ## Including other Taskfiles

internal/compiler/compiler.go

@@ -7,6 +7,7 @@ import (
 // Compiler handles compilation of a task before its execution.
 // E.g. variable merger, template processing, etc.
 type Compiler interface {
+	GetTaskfileVariables() (*taskfile.Vars, error)
 	GetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error)
 	FastGetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error)
 	HandleDynamicVar(v taskfile.Var, dir string) (string, error)

internal/compiler/v2/compiler_v2.go

@@ -30,6 +30,10 @@ type CompilerV2 struct {
 	muDynamicCache sync.Mutex
 }
 
+func (c *CompilerV2) GetTaskfileVariables() (*taskfile.Vars, error) {
+	return &taskfile.Vars{}, nil
+}
+
 // FastGetVariables is a no-op on v2
 func (c *CompilerV2) FastGetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error) {
 	return c.GetVariables(t, call)

internal/compiler/v3/compiler_v3.go

@@ -29,17 +29,23 @@ type CompilerV3 struct {
 	muDynamicCache sync.Mutex
 }
 
+func (c *CompilerV3) GetTaskfileVariables() (*taskfile.Vars, error) {
+	return c.getVariables(nil, nil, true)
+}
+
 func (c *CompilerV3) GetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error) {
-	return c.getVariables(t, call, true)
+	return c.getVariables(t, &call, true)
 }
 
 func (c *CompilerV3) FastGetVariables(t *taskfile.Task, call taskfile.Call) (*taskfile.Vars, error) {
-	return c.getVariables(t, call, false)
+	return c.getVariables(t, &call, false)
 }
 
-func (c *CompilerV3) getVariables(t *taskfile.Task, call taskfile.Call, evaluateShVars bool) (*taskfile.Vars, error) {
+func (c *CompilerV3) getVariables(t *taskfile.Task, call *taskfile.Call, evaluateShVars bool) (*taskfile.Vars, error) {
 	result := compiler.GetEnviron()
-	result.Set("TASK", taskfile.Var{Static: t.Task})
+	if t != nil {
+		result.Set("TASK", taskfile.Var{Static: t.Task})
+	}
 
 	getRangeFunc := func(dir string) func(k string, v taskfile.Var) error {
 		return func(k string, v taskfile.Var) error {
@@ -74,6 +80,11 @@ func (c *CompilerV3) getVariables(t *taskfile.Task, call taskfile.Call, evaluate
 	if err := c.TaskfileVars.Range(rangeFunc); err != nil {
 		return nil, err
 	}
+
+	if t == nil || call == nil {
+		return result, nil
+	}
+
 	if err := call.Vars.Range(rangeFunc); err != nil {
 		return nil, err
 	}

task.go

@@ -176,6 +176,23 @@ func (e *Executor) Setup() error {
 		}
 	}
 
+	if v >= 3.0 {
+		env, err := read.Dotenv(e.Compiler, e.Taskfile, e.Dir)
+		if err != nil {
+			return err
+		}
+
+		err = env.Range(func(key string, value taskfile.Var) error {
+			if _, ok := e.Taskfile.Env.Mapping[key]; !ok {
+				e.Taskfile.Env.Set(key, value)
+			}
+			return nil
+		})
+		if err != nil {
+			return err
+		}
+	}
+
 	if v < 2.1 && e.Taskfile.Output != "" {
 		return fmt.Errorf(`task: Taskfile option "output" is only available starting on Taskfile version v2.1`)
 	}

task_test.go

@@ -904,6 +904,44 @@ func TestDotenvShouldAllowMissingEnv(t *testing.T) {
 	tt.Run(t)
 }
 
+func TestDotenvHasLocalEnvInPath(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/dotenv/local_env_in_path",
+		Target:    "default",
+		TrimSpace: false,
+		Files: map[string]string{
+			"var.txt": "VAR='var_in_dot_env_1'\n",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestDotenvHasLocalVarInPath(t *testing.T) {
+	tt := fileContentTest{
+		Dir:       "testdata/dotenv/local_var_in_path",
+		Target:    "default",
+		TrimSpace: false,
+		Files: map[string]string{
+			"var.txt": "VAR='var_in_dot_env_3'\n",
+		},
+	}
+	tt.Run(t)
+}
+
+func TestDotenvHasEnvVarInPath(t *testing.T) {
+	os.Setenv("ENV_VAR", "testing")
+
+	tt := fileContentTest{
+		Dir:       "testdata/dotenv/env_var_in_path",
+		Target:    "default",
+		TrimSpace: false,
+		Files: map[string]string{
+			"var.txt": "VAR='var_in_dot_env_2'\n",
+		},
+	}
+	tt.Run(t)
+}
+
 func TestExitImmediately(t *testing.T) {
 	const dir = "testdata/exit_immediately"
 

taskfile/read/dotenv.go

@@ -0,0 +1,46 @@
+package read
+
+import (
+	"os"
+	"path/filepath"
+
+	"github.com/joho/godotenv"
+
+	"github.com/go-task/task/v3/internal/compiler"
+	"github.com/go-task/task/v3/internal/templater"
+	"github.com/go-task/task/v3/taskfile"
+)
+
+func Dotenv(c compiler.Compiler, tf *taskfile.Taskfile, dir string) (*taskfile.Vars, error) {
+	vars, err := c.GetTaskfileVariables()
+	if err != nil {
+		return nil, err
+	}
+
+	env := &taskfile.Vars{}
+
+	tr := templater.Templater{Vars: vars, RemoveNoValue: true}
+
+	for _, dotEnvPath := range tf.Dotenv {
+		dotEnvPath = tr.Replace(dotEnvPath)
+
+		if !filepath.IsAbs(dotEnvPath) {
+			dotEnvPath = filepath.Join(dir, dotEnvPath)
+		}
+		if _, err := os.Stat(dotEnvPath); os.IsNotExist(err) {
+			continue
+		}
+
+		envs, err := godotenv.Read(dotEnvPath)
+		if err != nil {
+			return nil, err
+		}
+		for key, value := range envs {
+			if _, ok := env.Mapping[key]; !ok {
+				env.Set(key, taskfile.Var{Static: value})
+			}
+		}
+	}
+
+	return env, nil
+}

taskfile/read/taskfile.go

@@ -7,7 +7,6 @@ import (
 	"path/filepath"
 	"runtime"
 
-	"github.com/joho/godotenv"
 	"gopkg.in/yaml.v3"
 
 	"github.com/go-task/task/v3/internal/templater"
@@ -37,27 +36,6 @@ func Taskfile(dir string, entrypoint string) (*taskfile.Taskfile, error) {
 		return nil, err
 	}
 
-	if v >= 3.0 {
-		for _, dotEnvPath := range t.Dotenv {
-			if !filepath.IsAbs(dotEnvPath) {
-				dotEnvPath = filepath.Join(dir, dotEnvPath)
-			}
-			if _, err := os.Stat(dotEnvPath); os.IsNotExist(err) {
-				continue
-			}
-
-			envs, err := godotenv.Read(dotEnvPath)
-			if err != nil {
-				return nil, err
-			}
-			for key, value := range envs {
-				if _, ok := t.Env.Mapping[key]; !ok {
-					t.Env.Set(key, taskfile.Var{Static: value})
-				}
-			}
-		}
-	}
-
 	err = t.Includes.Range(func(namespace string, includedTask taskfile.IncludedTaskfile) error {
 		if v >= 3.0 {
 			tr := templater.Templater{Vars: &taskfile.Vars{}, RemoveNoValue: true}

testdata/dotenv/env_var_in_path/.env.testing

@@ -0,0 +1 @@
+VAR_IN_DOTENV=var_in_dot_env_2

testdata/dotenv/env_var_in_path/Taskfile.yml

@@ -0,0 +1,8 @@
+version: "3"
+
+dotenv: [".env.{{.ENV_VAR}}"]
+
+tasks:
+  default:
+    cmds:
+      - echo "VAR='$VAR_IN_DOTENV'" > var.txt