Combine home dir resolving into path resolving.

Use filepath.Rel() instead of raw prefix checking.

dev/build

@@ -1,2 +1,2 @@
 #!/bin/bash
-go build -ldflags "-X main.version=dev-$(date +%F-%T)" -o /usr/local/bin/yeydev ./src
+go build -ldflags "-X main.version=dev-$(date +%F-%T)" -o /usr/local/bin/yey ./src

src/cmd/run/run.go

@@ -100,14 +100,15 @@ func getContainerWorkDir(yeyContext yey.Context) (string, error) {
 		return "", err
 	}
 
-	mounts, err := yeyContext.ResolveMounts()
-	if err != nil {
-		return "", err
-	}
+	for key, value := range yeyContext.Mounts {
+		// Where is work dir relatively to mount dir?
+		subDir, err := filepath.Rel(key, workDir)
+		if err != nil {
+			return "", err
+		}
 
-	for key, value := range mounts {
-		if strings.HasPrefix(workDir, key) {
-			subDir := strings.TrimPrefix(workDir, key)
+		// Is work dir within mount dir?
+		if !strings.HasPrefix(subDir, fmt.Sprintf("..%c", filepath.Separator)) {
 			return filepath.Join(value, subDir), nil
 		}
 	}

src/internal/context.go

@@ -1,9 +1,6 @@
 package yey
 
 import (
-	"path/filepath"
-
-	"github.com/mitchellh/go-homedir"
 	"gopkg.in/yaml.v2"
 )
 
@@ -83,34 +80,3 @@ func (c Context) String() string {
 	}
 	return string(buf)
 }
-
-func (c Context) ResolveMounts() (map[string]string, error) {
-	mounts := make(map[string]string, len(c.Mounts))
-	for key, value := range c.Mounts {
-		dir, err := resolveLocalDir(key)
-		if err != nil {
-			return nil, err
-		}
-		mounts[dir] = value
-	}
-	return mounts, nil
-}
-
-func resolveLocalDir(dir string) (string, error) {
-	var err error
-	if dir == "~" {
-		dir, err = homedir.Dir()
-	} else {
-		dir, err = homedir.Expand(dir)
-	}
-	if err != nil {
-		return "", err
-	}
-
-	dir, err = filepath.Abs(dir)
-	if err != nil {
-		return "", err
-	}
-
-	return dir, nil
-}

src/internal/contextFile.go

@@ -90,9 +90,16 @@ func parseContextFile(dir string, data []byte) (Contexts, error) {
 	}
 
 	if dir != "" {
-		contexts.Context = resolveContextPaths(dir, contexts.Context)
+		var err error
+		contexts.Context, err = resolveContextPaths(dir, contexts.Context)
+		if err != nil {
+			return Contexts{}, err
+		}
 		for name, context := range contexts.Named {
-			contexts.Named[name] = resolveContextPaths(dir, context)
+			contexts.Named[name], err = resolveContextPaths(dir, context)
+			if err != nil {
+				return Contexts{}, err
+			}
 		}
 	}
 
@@ -145,24 +152,54 @@ func LoadContexts() (Contexts, error) {
 	return contexts, nil
 }
 
-func resolveContextPaths(dir string, context Context) Context {
+func resolveContextPaths(dir string, context Context) (Context, error) {
 	clone := context.Clone()
-	clone.Build.Dockerfile = resolvePath(dir, context.Build.Dockerfile)
-	clone.Build.Context = resolvePath(dir, clone.Build.Context)
-	for key, value := range clone.Mounts {
-		clone.Mounts[resolvePath(dir, key)] = value
+
+	// Resolve dockerfile path
+	var err error
+	clone.Build.Dockerfile, err = resolvePath(dir, context.Build.Dockerfile)
+	if err != nil {
+		return Context{}, err
+	}
+
+	// Resolve build context dir
+	clone.Build.Context, err = resolvePath(dir, clone.Build.Context)
+	if err != nil {
+		return Context{}, err
+	}
+
+	// Resolve mount dirs
+	clone.Mounts = make(map[string]string, len(context.Mounts))
+	for key, value := range context.Mounts {
+		key, err = resolvePath(dir, key)
+		if err != nil {
+			return Context{}, err
+		}
+		clone.Mounts[key] = value
 	}
-	return clone
+
+	return clone, nil
 }
 
-func resolvePath(dir, path string) string {
+func resolvePath(dir, path string) (string, error) {
 	if path == "" {
-		return ""
+		return "", nil
+	}
+
+	// Resolve home dir
+	var err error
+	if path == "~" {
+		path, err = homedir.Dir()
+	} else {
+		path, err = homedir.Expand(path)
+	}
+	if err != nil {
+		return "", err
 	}
 
 	if filepath.IsAbs(path) {
-		return path
+		return path, nil
 	}
 
-	return filepath.Join(dir, path)
+	return filepath.Join(dir, path), nil
 }

src/internal/docker/cli.go

@@ -129,11 +129,7 @@ func runContainer(ctx context.Context, yeyCtx yey.Context, containerName, workDi
 	}
 
 	// Mount binds
-	mounts, err := yeyCtx.ResolveMounts()
-	if err != nil {
-		return err
-	}
-	for key, value := range mounts {
+	for key, value := range yeyCtx.Mounts {
 		args = append(
 			args,
 			"--volume",