From 837ced40470c99741073ae5dd4d187587b8a6325 Mon Sep 17 00:00:00 2001
From: flat20 <andreas.reuterberg@gmail.com>
Date: Tue, 18 Apr 2017 19:43:39 +0100
Subject: [PATCH] Updated getPkgPath to use package filepath, rather than path.
 Fixes an issue with os.Getwd() returning a random letter case drive letter on
 Windows, making the working directory unequal to GOPATH.

---
 parser/parser.go         | 30 ++++++++++++++++++++++++++
 parser/parser_test.go    | 26 +++++++++++++++++++++++
 parser/parser_unix.go    | 30 ++------------------------
 parser/parser_windows.go | 46 ++++++++--------------------------------
 4 files changed, 67 insertions(+), 65 deletions(-)
 create mode 100644 parser/parser_test.go

diff --git a/parser/parser.go b/parser/parser.go
index 1c0b94c..b8b9852 100644
--- a/parser/parser.go
+++ b/parser/parser.go
@@ -1,9 +1,13 @@
 package parser
 
 import (
+	"fmt"
 	"go/ast"
 	"go/parser"
 	"go/token"
+	"os"
+	"path"
+	"path/filepath"
 	"strings"
 )
 
@@ -89,3 +93,29 @@ func (p *Parser) Parse(fname string, isDir bool) error {
 	}
 	return nil
 }
+
+func getPkgPath(fname string, isDir bool) (string, error) {
+	fname, err := filepath.Abs(fname)
+	if err != nil {
+		return "", err
+	}
+
+	for _, p := range filepath.SplitList(os.Getenv("GOPATH")) {
+		gopath := filepath.Join(p, "src")
+		pkg, err := filepath.Rel(gopath, fname)
+		if err != nil {
+			continue
+		}
+
+		if pkg != fname {
+			p := normalizePath(pkg)
+
+			if !isDir {
+				return path.Dir(p), nil
+			}
+			return p, nil
+		}
+	}
+
+	return "", fmt.Errorf("file '%v' is not in GOPATH", fname)
+}
diff --git a/parser/parser_test.go b/parser/parser_test.go
new file mode 100644
index 0000000..7be4654
--- /dev/null
+++ b/parser/parser_test.go
@@ -0,0 +1,26 @@
+package parser
+
+import "testing"
+
+func TestGetPkgPath(t *testing.T) {
+	cases := []struct {
+		fname string
+		isDir bool
+	}{
+		{"parser.go", false},
+		{".", true},
+	}
+	exp := "github.com/mailru/easyjson/parser"
+
+	for _, tc := range cases {
+
+		pkg, err := getPkgPath(tc.fname, tc.isDir)
+		if err != nil {
+			t.Error(err)
+		}
+		if pkg != exp {
+			t.Errorf("in: \"%s\" isDir: %v want: %s got: %s", tc.fname, tc.isDir, exp, pkg)
+		}
+	}
+
+}
diff --git a/parser/parser_unix.go b/parser/parser_unix.go
index a1b9d84..a5a9451 100644
--- a/parser/parser_unix.go
+++ b/parser/parser_unix.go
@@ -2,32 +2,6 @@
 
 package parser
 
-import (
-	"fmt"
-	"os"
-	"path"
-	"strings"
-)
-
-func getPkgPath(fname string, isDir bool) (string, error) {
-	if !path.IsAbs(fname) {
-		pwd, err := os.Getwd()
-		if err != nil {
-			return "", err
-		}
-		fname = path.Join(pwd, fname)
-	}
-
-	for _, p := range strings.Split(os.Getenv("GOPATH"), ":") {
-		prefix := path.Join(p, "src") + "/"
-		if rel := strings.TrimPrefix(fname, prefix); rel != fname {
-			if !isDir {
-				return path.Dir(rel), nil
-			} else {
-				return path.Clean(rel), nil
-			}
-		}
-	}
-
-	return "", fmt.Errorf("file '%v' is not in GOPATH", fname)
+func normalizePath(path string) string {
+	return path
 }
diff --git a/parser/parser_windows.go b/parser/parser_windows.go
index 64974aa..cd4be7c 100644
--- a/parser/parser_windows.go
+++ b/parser/parser_windows.go
@@ -1,37 +1,9 @@
-package parser
-
-import (
-	"fmt"
-	"os"
-	"path"
-	"strings"
-)
-
-func normalizePath(path string) string {
-	return strings.Replace(path, "\\", "/", -1)
-}
-
-func getPkgPath(fname string, isDir bool) (string, error) {
-	if !path.IsAbs(fname) {
-		pwd, err := os.Getwd()
-		if err != nil {
-			return "", err
-		}
-		fname = path.Join(pwd, fname)
-	}
-
-	fname = normalizePath(fname)
-
-	for _, p := range strings.Split(os.Getenv("GOPATH"), ";") {
-		prefix := path.Join(normalizePath(p), "src") + "/"
-		if rel := strings.TrimPrefix(fname, prefix); rel != fname {
-			if !isDir {
-				return path.Dir(rel), nil
-			} else {
-				return path.Clean(rel), nil
-			}
-		}
-	}
-
-	return "", fmt.Errorf("file '%v' is not in GOPATH", fname)
-}
+package parser
+
+import (
+	"strings"
+)
+
+func normalizePath(path string) string {
+	return strings.Replace(path, "\\", "/", -1)
+}