restructure code that derives name for executable and reformat script…

… file, remove whitespaces and set tabs as indent

src/cmd/go/internal/run/run.go

@@ -8,7 +8,7 @@ package run
 import (
 	"fmt"
 	"os"
-	"path/filepath"
+	"path"
 	"strings"
 
 	"cmd/go/internal/base"
@@ -23,7 +23,7 @@ var CmdRun = &base.Command{
 	Short:     "compile and run Go program",
 	Long: `
 Run compiles and runs the named main Go package.
-Typically the package is specified as a list of .go source files from a single directory,
+Typically the package is specified as a list of .go source files,
 but it may also be an import path, file system path, or pattern
 matching a single known package, as in 'go run .' or 'go run my/cmd'.
 
@@ -95,10 +95,10 @@ func runRun(cmd *base.Command, args []string) {
 		base.Fatalf("go run: no go files listed")
 	}
 	cmdArgs := args[i:]
-
 	if p.Error != nil {
 		base.Fatalf("%s", p.Error)
 	}
+
 	p.Internal.OmitDebug = true
 	if len(p.DepsErrors) > 0 {
 		// Since these are errors in dependencies,
@@ -118,25 +118,25 @@ func runRun(cmd *base.Command, args []string) {
 		base.Fatalf("go run: cannot run non-main package")
 	}
 	p.Target = "" // must build - not up to date
-	var src string
-	if len(p.GoFiles) > 0 {
-		src = p.GoFiles[0]
-	} else if len(p.CgoFiles) > 0 {
-		src = p.CgoFiles[0]
-	} else {
-		// this case could only happen if the provided source uses cgo
-		// while cgo is disabled.
-		hint := ""
-		if !cfg.BuildContext.CgoEnabled {
-			hint = " (cgo is disabled)"
+	if p.Internal.CmdlineFiles {
+		//set executable name if go file is given as cmd-argument
+		var src string
+		if len(p.GoFiles) > 0 {
+			src = p.GoFiles[0]
+		} else if len(p.CgoFiles) > 0 {
+			src = p.CgoFiles[0]
+		} else {
+			// this case could only happen if the provided source uses cgo
+			// while cgo is disabled.
+			hint := ""
+			if !cfg.BuildContext.CgoEnabled {
+				hint = " (cgo is disabled)"
+			}
+			base.Fatalf("go run: no suitable source files%s", hint)
 		}
-		base.Fatalf("go run: no suitable source files%s", hint)
-	}
-	p.Internal.ExeName = src[:len(src)-len(".go")] // set name of first go file as temporary executable name
-	if len(args) == 1 && args[0] == "." {
-		p.Internal.ExeName = p.Dir // set name of directory as temporary executable name
-	} else if len(args) == 1 && filepath.Ext(args[0]) == "" {
-		p.Internal.ExeName = p.Dir // set name of directoy as temporary executable name if args[0] is a directory.
+		p.Internal.ExeName = src[:len(src)-len(".go")]
+	} else {
+		p.Internal.ExeName = path.Base(p.ImportPath)
 	}
 	a1 := b.LinkAction(work.ModeBuild, work.ModeBuild, p)
 	a := &work.Action{Mode: "go run", Func: buildRunProgram, Args: cmdArgs, Deps: []*work.Action{a1}}

src/cmd/go/testdata/script/run_set_executable_name.txt

@@ -16,30 +16,30 @@ stderr 'z'
 -- m/x/y/z/foo.go --
 package main
 import(
-    "os"
+	"os"
 	"path/filepath"
 )
-func main() { 
-    println(filepath.Base(os.Args[0])) 
+func main() {
+	println(filepath.Base(os.Args[0]))
 }
 
 -- m/x/y/z/foo.go --
 package main
 import(
-    "os"
+	"os"
 	"path/filepath"
 )
-func main() { 
-    println(filepath.Base(os.Args[0])) 
+func main() {
+	println(filepath.Base(os.Args[0]))
 }
 
 -- m/x/y/z/foo.go --
 package main
 import(
-    "os"
+	"os"
 	"path/filepath"
 )
-func main() { 
-    println(filepath.Base(os.Args[0])) 
+func main() {
+	println(filepath.Base(os.Args[0]))
 }