[pkg] all your deps are vendored to us

1 files changed, 1818 insertions, 0 deletions

diff --git a/vendor/golang.org/x/tools/go/ast/astutil/imports_test.go b/vendor/golang.org/x/tools/go/ast/astutil/imports_test.go
new file mode 100644
index 0000000..8bc3480
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/ast/astutil/imports_test.go
@@ -0,0 +1,1818 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package astutil
+
+import (
+	"bytes"
+	"go/ast"
+	"go/format"
+	"go/parser"
+	"go/token"
+	"reflect"
+	"strconv"
+	"testing"
+)
+
+var fset = token.NewFileSet()
+
+func parse(t *testing.T, name, in string) *ast.File {
+	file, err := parser.ParseFile(fset, name, in, parser.ParseComments)
+	if err != nil {
+		t.Fatalf("%s parse: %v", name, err)
+	}
+	return file
+}
+
+func print(t *testing.T, name string, f *ast.File) string {
+	var buf bytes.Buffer
+	if err := format.Node(&buf, fset, f); err != nil {
+		t.Fatalf("%s gofmt: %v", name, err)
+	}
+	return string(buf.Bytes())
+}
+
+type test struct {
+	name       string
+	renamedPkg string
+	pkg        string
+	in         string
+	out        string
+	broken     bool // known broken
+}
+
+var addTests = []test{
+	{
+		name: "leave os alone",
+		pkg:  "os",
+		in: `package main
+
+import (
+	"os"
+)
+`,
+		out: `package main
+
+import (
+	"os"
+)
+`,
+	},
+	{
+		name: "import.1",
+		pkg:  "os",
+		in: `package main
+`,
+		out: `package main
+
+import "os"
+`,
+	},
+	{
+		name: "import.2",
+		pkg:  "os",
+		in: `package main
+
+// Comment
+import "C"
+`,
+		out: `package main
+
+// Comment
+import "C"
+import "os"
+`,
+	},
+	{
+		name: "import.3",
+		pkg:  "os",
+		in: `package main
+
+// Comment
+import "C"
+
+import (
+	"io"
+	"utf8"
+)
+`,
+		out: `package main
+
+// Comment
+import "C"
+
+import (
+	"io"
+	"os"
+	"utf8"
+)
+`,
+	},
+	{
+		name: "import.17",
+		pkg:  "x/y/z",
+		in: `package main
+
+// Comment
+import "C"
+
+import (
+	"a"
+	"b"
+
+	"x/w"
+
+	"d/f"
+)
+`,
+		out: `package main
+
+// Comment
+import "C"
+
+import (
+	"a"
+	"b"
+
+	"x/w"
+	"x/y/z"
+
+	"d/f"
+)
+`,
+	},
+	{
+		name: "issue #19190",
+		pkg:  "x.org/y/z",
+		in: `package main
+
+// Comment
+import "C"
+
+import (
+	"bytes"
+	"os"
+
+	"d.com/f"
+)
+`,
+		out: `package main
+
+// Comment
+import "C"
+
+import (
+	"bytes"
+	"os"
+
+	"d.com/f"
+	"x.org/y/z"
+)
+`,
+	},
+	{
+		name: "issue #19190 with existing grouped import packages",
+		pkg:  "x.org/y/z",
+		in: `package main
+
+// Comment
+import "C"
+
+import (
+	"bytes"
+	"os"
+
+	"c.com/f"
+	"d.com/f"
+
+	"y.com/a"
+	"y.com/b"
+	"y.com/c"
+)
+`,
+		out: `package main
+
+// Comment
+import "C"
+
+import (
+	"bytes"
+	"os"
+
+	"c.com/f"
+	"d.com/f"
+	"x.org/y/z"
+
+	"y.com/a"
+	"y.com/b"
+	"y.com/c"
+)
+`,
+	},
+	{
+		name: "issue #19190 - match score is still respected",
+		pkg:  "y.org/c",
+		in: `package main
+
+import (
+	"x.org/a"
+
+	"y.org/b"
+)
+`,
+		out: `package main
+
+import (
+	"x.org/a"
+
+	"y.org/b"
+	"y.org/c"
+)
+`,
+	},
+	{
+		name: "import into singular group",
+		pkg:  "bytes",
+		in: `package main
+
+import "os"
+
+`,
+		out: `package main
+
+import (
+	"bytes"
+	"os"
+)
+`,
+	},
+	{
+		name: "import into singular group with comment",
+		pkg:  "bytes",
+		in: `package main
+
+import /* why */ /* comment here? */ "os"
+
+`,
+		out: `package main
+
+import /* why */ /* comment here? */ (
+	"bytes"
+	"os"
+)
+`,
+	},
+	{
+		name: "import into group with leading comment",
+		pkg:  "strings",
+		in: `package main
+
+import (
+	// comment before bytes
+	"bytes"
+	"os"
+)
+
+`,
+		out: `package main
+
+import (
+	// comment before bytes
+	"bytes"
+	"os"
+	"strings"
+)
+`,
+	},
+	{
+		name:       "",
+		renamedPkg: "fmtpkg",
+		pkg:        "fmt",
+		in: `package main
+
+import "os"
+
+`,
+		out: `package main
+
+import (
+	fmtpkg "fmt"
+	"os"
+)
+`,
+	},
+	{
+		name: "struct comment",
+		pkg:  "time",
+		in: `package main
+
+// This is a comment before a struct.
+type T struct {
+	t  time.Time
+}
+`,
+		out: `package main
+
+import "time"
+
+// This is a comment before a struct.
+type T struct {
+	t time.Time
+}
+`,
+	},
+	{
+		name: "issue 8729 import C",
+		pkg:  "time",
+		in: `package main
+
+import "C"
+
+// comment
+type T time.Time
+`,
+		out: `package main
+
+import "C"
+import "time"
+
+// comment
+type T time.Time
+`,
+	},
+	{
+		name: "issue 8729 empty import",
+		pkg:  "time",
+		in: `package main
+
+import ()
+
+// comment
+type T time.Time
+`,
+		out: `package main
+
+import "time"
+
+// comment
+type T time.Time
+`,
+	},
+	{
+		name: "issue 8729 comment on package line",
+		pkg:  "time",
+		in: `package main // comment
+
+type T time.Time
+`,
+		out: `package main // comment
+import "time"
+
+type T time.Time
+`,
+	},
+	{
+		name: "issue 8729 comment after package",
+		pkg:  "time",
+		in: `package main
+// comment
+
+type T time.Time
+`,
+		out: `package main
+
+import "time"
+
+// comment
+
+type T time.Time
+`,
+	},
+	{
+		name: "issue 8729 comment before and on package line",
+		pkg:  "time",
+		in: `// comment before
+package main // comment on
+
+type T time.Time
+`,
+		out: `// comment before
+package main // comment on
+import "time"
+
+type T time.Time
+`,
+	},
+
+	// Issue 9961: Match prefixes using path segments rather than bytes
+	{
+		name: "issue 9961",
+		pkg:  "regexp",
+		in: `package main
+
+import (
+	"flag"
+	"testing"
+
+	"rsc.io/p"
+)
+`,
+		out: `package main
+
+import (
+	"flag"
+	"regexp"
+	"testing"
+
+	"rsc.io/p"
+)
+`,
+	},
+	// Issue 10337: Preserve comment position
+	{
+		name: "issue 10337",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	"bytes" // a
+	"log" // c
+)
+`,
+		out: `package main
+
+import (
+	"bytes" // a
+	"fmt"
+	"log" // c
+)
+`,
+	},
+	{
+		name: "issue 10337 new import at the start",
+		pkg:  "bytes",
+		in: `package main
+
+import (
+	"fmt" // b
+	"log" // c
+)
+`,
+		out: `package main
+
+import (
+	"bytes"
+	"fmt" // b
+	"log" // c
+)
+`,
+	},
+	{
+		name: "issue 10337 new import at the end",
+		pkg:  "log",
+		in: `package main
+
+import (
+	"bytes" // a
+	"fmt" // b
+)
+`,
+		out: `package main
+
+import (
+	"bytes" // a
+	"fmt"   // b
+	"log"
+)
+`,
+	},
+	// Issue 14075: Merge import declarations
+	{
+		name: "issue 14075",
+		pkg:  "bufio",
+		in: `package main
+
+import "bytes"
+import "fmt"
+`,
+		out: `package main
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+)
+`,
+	},
+	{
+		name: "issue 14075 update position",
+		pkg:  "bufio",
+		in: `package main
+
+import "bytes"
+import (
+	"fmt"
+)
+`,
+		out: `package main
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+)
+`,
+	},
+	{
+		name: `issue 14075 ignore import "C"`,
+		pkg:  "bufio",
+		in: `package main
+
+// Comment
+import "C"
+
+import "bytes"
+import "fmt"
+`,
+		out: `package main
+
+// Comment
+import "C"
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+)
+`,
+	},
+	{
+		name: `issue 14075 ignore adjacent import "C"`,
+		pkg:  "bufio",
+		in: `package main
+
+// Comment
+import "C"
+import "fmt"
+`,
+		out: `package main
+
+// Comment
+import "C"
+import (
+	"bufio"
+	"fmt"
+)
+`,
+	},
+	{
+		name: `issue 14075 ignore adjacent import "C" (without factored import)`,
+		pkg:  "bufio",
+		in: `package main
+
+// Comment
+import "C"
+import "fmt"
+`,
+		out: `package main
+
+// Comment
+import "C"
+import (
+	"bufio"
+	"fmt"
+)
+`,
+	},
+	{
+		name: `issue 14075 ignore single import "C"`,
+		pkg:  "bufio",
+		in: `package main
+
+// Comment
+import "C"
+`,
+		out: `package main
+
+// Comment
+import "C"
+import "bufio"
+`,
+	},
+	{
+		name: `issue 17212 several single-import lines with shared prefix ending in a slash`,
+		pkg:  "net/http",
+		in: `package main
+
+import "bufio"
+import "net/url"
+`,
+		out: `package main
+
+import (
+	"bufio"
+	"net/http"
+	"net/url"
+)
+`,
+	},
+	{
+		name: `issue 17212 block imports lines with shared prefix ending in a slash`,
+		pkg:  "net/http",
+		in: `package main
+
+import (
+	"bufio"
+	"net/url"
+)
+`,
+		out: `package main
+
+import (
+	"bufio"
+	"net/http"
+	"net/url"
+)
+`,
+	},
+	{
+		name: `issue 17213 many single-import lines`,
+		pkg:  "fmt",
+		in: `package main
+
+import "bufio"
+import "bytes"
+import "errors"
+`,
+		out: `package main
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+)
+`,
+	},
+}
+
+func TestAddImport(t *testing.T) {
+	for _, test := range addTests {
+		file := parse(t, test.name, test.in)
+		var before bytes.Buffer
+		ast.Fprint(&before, fset, file, nil)
+		AddNamedImport(fset, file, test.renamedPkg, test.pkg)
+		if got := print(t, test.name, file); got != test.out {
+			if test.broken {
+				t.Logf("%s is known broken:\ngot: %s\nwant: %s", test.name, got, test.out)
+			} else {
+				t.Errorf("%s:\ngot: %s\nwant: %s", test.name, got, test.out)
+			}
+			var after bytes.Buffer
+			ast.Fprint(&after, fset, file, nil)
+
+			t.Logf("AST before:\n%s\nAST after:\n%s\n", before.String(), after.String())
+		}
+	}
+}
+
+func TestDoubleAddImport(t *testing.T) {
+	file := parse(t, "doubleimport", "package main\n")
+	AddImport(fset, file, "os")
+	AddImport(fset, file, "bytes")
+	want := `package main
+
+import (
+	"bytes"
+	"os"
+)
+`
+	if got := print(t, "doubleimport", file); got != want {
+		t.Errorf("got: %s\nwant: %s", got, want)
+	}
+}
+
+func TestDoubleAddNamedImport(t *testing.T) {
+	file := parse(t, "doublenamedimport", "package main\n")
+	AddNamedImport(fset, file, "o", "os")
+	AddNamedImport(fset, file, "i", "io")
+	want := `package main
+
+import (
+	i "io"
+	o "os"
+)
+`
+	if got := print(t, "doublenamedimport", file); got != want {
+		t.Errorf("got: %s\nwant: %s", got, want)
+	}
+}
+
+// Part of issue 8729.
+func TestDoubleAddImportWithDeclComment(t *testing.T) {
+	file := parse(t, "doubleimport", `package main
+
+import (
+)
+
+// comment
+type I int
+`)
+	// The AddImport order here matters.
+	AddImport(fset, file, "golang.org/x/tools/go/ast/astutil")
+	AddImport(fset, file, "os")
+	want := `package main
+
+import (
+	"golang.org/x/tools/go/ast/astutil"
+	"os"
+)
+
+// comment
+type I int
+`
+	if got := print(t, "doubleimport_with_decl_comment", file); got != want {
+		t.Errorf("got: %s\nwant: %s", got, want)
+	}
+}
+
+var deleteTests = []test{
+	{
+		name: "import.4",
+		pkg:  "os",
+		in: `package main
+
+import (
+	"os"
+)
+`,
+		out: `package main
+`,
+	},
+	{
+		name: "import.5",
+		pkg:  "os",
+		in: `package main
+
+// Comment
+import "C"
+import "os"
+`,
+		out: `package main
+
+// Comment
+import "C"
+`,
+	},
+	{
+		name: "import.6",
+		pkg:  "os",
+		in: `package main
+
+// Comment
+import "C"
+
+import (
+	"io"
+	"os"
+	"utf8"
+)
+`,
+		out: `package main
+
+// Comment
+import "C"
+
+import (
+	"io"
+	"utf8"
+)
+`,
+	},
+	{
+		name: "import.7",
+		pkg:  "io",
+		in: `package main
+
+import (
+	"io"   // a
+	"os"   // b
+	"utf8" // c
+)
+`,
+		out: `package main
+
+import (
+	// a
+	"os"   // b
+	"utf8" // c
+)
+`,
+	},
+	{
+		name: "import.8",
+		pkg:  "os",
+		in: `package main
+
+import (
+	"io"   // a
+	"os"   // b
+	"utf8" // c
+)
+`,
+		out: `package main
+
+import (
+	"io" // a
+	// b
+	"utf8" // c
+)
+`,
+	},
+	{
+		name: "import.9",
+		pkg:  "utf8",
+		in: `package main
+
+import (
+	"io"   // a
+	"os"   // b
+	"utf8" // c
+)
+`,
+		out: `package main
+
+import (
+	"io" // a
+	"os" // b
+	// c
+)
+`,
+	},
+	{
+		name: "import.10",
+		pkg:  "io",
+		in: `package main
+
+import (
+	"io"
+	"os"
+	"utf8"
+)
+`,
+		out: `package main
+
+import (
+	"os"
+	"utf8"
+)
+`,
+	},
+	{
+		name: "import.11",
+		pkg:  "os",
+		in: `package main
+
+import (
+	"io"
+	"os"
+	"utf8"
+)
+`,
+		out: `package main
+
+import (
+	"io"
+	"utf8"
+)
+`,
+	},
+	{
+		name: "import.12",
+		pkg:  "utf8",
+		in: `package main
+
+import (
+	"io"
+	"os"
+	"utf8"
+)
+`,
+		out: `package main
+
+import (
+	"io"
+	"os"
+)
+`,
+	},
+	{
+		name: "handle.raw.quote.imports",
+		pkg:  "os",
+		in:   "package main\n\nimport `os`",
+		out: `package main
+`,
+	},
+	{
+		name: "import.13",
+		pkg:  "io",
+		in: `package main
+
+import (
+	"fmt"
+
+	"io"
+	"os"
+	"utf8"
+
+	"go/format"
+)
+`,
+		out: `package main
+
+import (
+	"fmt"
+
+	"os"
+	"utf8"
+
+	"go/format"
+)
+`,
+	},
+	{
+		name: "import.14",
+		pkg:  "io",
+		in: `package main
+
+import (
+	"fmt" // a
+
+	"io"   // b
+	"os"   // c
+	"utf8" // d
+
+	"go/format" // e
+)
+`,
+		out: `package main
+
+import (
+	"fmt" // a
+
+	// b
+	"os"   // c
+	"utf8" // d
+
+	"go/format" // e
+)
+`,
+	},
+	{
+		name: "import.15",
+		pkg:  "double",
+		in: `package main
+
+import (
+	"double"
+	"double"
+)
+`,
+		out: `package main
+`,
+	},
+	{
+		name: "import.16",
+		pkg:  "bubble",
+		in: `package main
+
+import (
+	"toil"
+	"bubble"
+	"bubble"
+	"trouble"
+)
+`,
+		out: `package main
+
+import (
+	"toil"
+	"trouble"
+)
+`,
+	},
+	{
+		name: "import.17",
+		pkg:  "quad",
+		in: `package main
+
+import (
+	"quad"
+	"quad"
+)
+
+import (
+	"quad"
+	"quad"
+)
+`,
+		out: `package main
+`,
+	},
+	{
+		name:       "import.18",
+		renamedPkg: "x",
+		pkg:        "fmt",
+		in: `package main
+
+import (
+	"fmt"
+	x "fmt"
+)
+`,
+		out: `package main
+
+import (
+	"fmt"
+)
+`,
+	},
+	{
+		name:       "import.18",
+		renamedPkg: "x",
+		pkg:        "fmt",
+		in: `package main
+
+import x "fmt"
+import y "fmt"
+`,
+		out: `package main
+
+import y "fmt"
+`,
+	},
+	// Issue #15432, #18051
+	{
+		name: "import.19",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	"fmt"
+
+	// Some comment.
+	"io"
+)`,
+		out: `package main
+
+import (
+	// Some comment.
+	"io"
+)
+`,
+	},
+	{
+		name: "import.20",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	"fmt"
+
+	// Some
+	// comment.
+	"io"
+)`,
+		out: `package main
+
+import (
+	// Some
+	// comment.
+	"io"
+)
+`,
+	},
+	{
+		name: "import.21",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	"fmt"
+
+	/*
+		Some
+		comment.
+	*/
+	"io"
+)`,
+		out: `package main
+
+import (
+	/*
+		Some
+		comment.
+	*/
+	"io"
+)
+`,
+	},
+	{
+		name: "import.22",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	/* Some */
+	// comment.
+	"io"
+	"fmt"
+)`,
+		out: `package main
+
+import (
+	/* Some */
+	// comment.
+	"io"
+)
+`,
+	},
+	{
+		name: "import.23",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	// comment 1
+	"fmt"
+	// comment 2
+	"io"
+)`,
+		out: `package main
+
+import (
+	// comment 2
+	"io"
+)
+`,
+	},
+	{
+		name: "import.24",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	"fmt" // comment 1
+	"io" // comment 2
+)`,
+		out: `package main
+
+import (
+	"io" // comment 2
+)
+`,
+	},
+	{
+		name: "import.25",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	"fmt"
+	/* comment */ "io"
+)`,
+		out: `package main
+
+import (
+	/* comment */ "io"
+)
+`,
+	},
+	{
+		name: "import.26",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	"fmt"
+	"io" /* comment */
+)`,
+		out: `package main
+
+import (
+	"io" /* comment */
+)
+`,
+	},
+	{
+		name: "import.27",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	"fmt" /* comment */
+	"io"
+)`,
+		out: `package main
+
+import (
+	"io"
+)
+`,
+	},
+	{
+		name: "import.28",
+		pkg:  "fmt",
+		in: `package main
+
+import (
+	/* comment */  "fmt"
+	"io"
+)`,
+		out: `package main
+
+import (
+	"io"
+)
+`,
+	},
+	{
+		name: "import.29",
+		pkg:  "fmt",
+		in: `package main
+
+// comment 1
+import (
+	"fmt"
+	"io" // comment 2
+)`,
+		out: `package main
+
+// comment 1
+import (
+	"io" // comment 2
+)
+`,
+	},
+	{
+		name: "import.30",
+		pkg:  "fmt",
+		in: `package main
+
+// comment 1
+import (
+	"fmt" // comment 2
+	"io"
+)`,
+		out: `package main
+
+// comment 1
+import (
+	"io"
+)
+`,
+	},
+	{
+		name: "import.31",
+		pkg:  "fmt",
+		in: `package main
+
+// comment 1
+import (
+	"fmt"
+	/* comment 2 */ "io"
+)`,
+		out: `package main
+
+// comment 1
+import (
+	/* comment 2 */ "io"
+)
+`,
+	},
+	{
+		name:       "import.32",
+		pkg:        "fmt",
+		renamedPkg: "f",
+		in: `package main
+
+// comment 1
+import (
+	f "fmt"
+	/* comment 2 */ i "io"
+)`,
+		out: `package main
+
+// comment 1
+import (
+	/* comment 2 */ i "io"
+)
+`,
+	},
+	{
+		name:       "import.33",
+		pkg:        "fmt",
+		renamedPkg: "f",
+		in: `package main
+
+// comment 1
+import (
+	/* comment 2 */ f "fmt"
+	i "io"
+)`,
+		out: `package main
+
+// comment 1
+import (
+	i "io"
+)
+`,
+	},
+	{
+		name:       "import.34",
+		pkg:        "fmt",
+		renamedPkg: "f",
+		in: `package main
+
+// comment 1
+import (
+	f "fmt" /* comment 2 */
+	i "io"
+)`,
+		out: `package main
+
+// comment 1
+import (
+	i "io"
+)
+`,
+	},
+	{
+		name: "import.35",
+		pkg:  "fmt",
+		in: `package main
+
+// comment 1
+import (
+	"fmt"
+	// comment 2
+	"io"
+)`,
+		out: `package main
+
+// comment 1
+import (
+	// comment 2
+	"io"
+)
+`,
+	},
+	{
+		name: "import.36",
+		pkg:  "fmt",
+		in: `package main
+
+/* comment 1 */
+import (
+	"fmt"
+	/* comment 2 */
+	"io"
+)`,
+		out: `package main
+
+/* comment 1 */
+import (
+	/* comment 2 */
+	"io"
+)
+`,
+	},
+
+	// Issue 20229: MergeLine panic on weird input
+	{
+		name: "import.37",
+		pkg:  "io",
+		in: `package main
+import("_"
+"io")`,
+		out: `package main
+
+import (
+	"_"
+)
+`,
+	},
+}
+
+func TestDeleteImport(t *testing.T) {
+	for _, test := range deleteTests {
+		file := parse(t, test.name, test.in)
+		DeleteNamedImport(fset, file, test.renamedPkg, test.pkg)
+		if got := print(t, test.name, file); got != test.out {
+			t.Errorf("%s:\ngot: %s\nwant: %s", test.name, got, test.out)
+		}
+	}
+}
+
+type rewriteTest struct {
+	name   string
+	srcPkg string
+	dstPkg string
+	in     string
+	out    string
+}
+
+var rewriteTests = []rewriteTest{
+	{
+		name:   "import.13",
+		srcPkg: "utf8",
+		dstPkg: "encoding/utf8",
+		in: `package main
+
+import (
+	"io"
+	"os"
+	"utf8" // thanks ken
+)
+`,
+		out: `package main
+
+import (
+	"encoding/utf8" // thanks ken
+	"io"
+	"os"
+)
+`,
+	},
+	{
+		name:   "import.14",
+		srcPkg: "asn1",
+		dstPkg: "encoding/asn1",
+		in: `package main
+
+import (
+	"asn1"
+	"crypto"
+	"crypto/rsa"
+	_ "crypto/sha1"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"time"
+)
+
+var x = 1
+`,
+		out: `package main
+
+import (
+	"crypto"
+	"crypto/rsa"
+	_ "crypto/sha1"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/asn1"
+	"time"
+)
+
+var x = 1
+`,
+	},
+	{
+		name:   "import.15",
+		srcPkg: "url",
+		dstPkg: "net/url",
+		in: `package main
+
+import (
+	"bufio"
+	"net"
+	"path"
+	"url"
+)
+
+var x = 1 // comment on x, not on url
+`,
+		out: `package main
+
+import (
+	"bufio"
+	"net"
+	"net/url"
+	"path"
+)
+
+var x = 1 // comment on x, not on url
+`,
+	},
+	{
+		name:   "import.16",
+		srcPkg: "http",
+		dstPkg: "net/http",
+		in: `package main
+
+import (
+	"flag"
+	"http"
+	"log"
+	"text/template"
+)
+
+var addr = flag.String("addr", ":1718", "http service address") // Q=17, R=18
+`,
+		out: `package main
+
+import (
+	"flag"
+	"log"
+	"net/http"
+	"text/template"
+)
+
+var addr = flag.String("addr", ":1718", "http service address") // Q=17, R=18
+`,
+	},
+}
+
+func TestRewriteImport(t *testing.T) {
+	for _, test := range rewriteTests {
+		file := parse(t, test.name, test.in)
+		RewriteImport(fset, file, test.srcPkg, test.dstPkg)
+		if got := print(t, test.name, file); got != test.out {
+			t.Errorf("%s:\ngot: %s\nwant: %s", test.name, got, test.out)
+		}
+	}
+}
+
+var importsTests = []struct {
+	name string
+	in   string
+	want [][]string
+}{
+	{
+		name: "no packages",
+		in: `package foo
+`,
+		want: nil,
+	},
+	{
+		name: "one group",
+		in: `package foo
+
+import (
+	"fmt"
+	"testing"
+)
+`,
+		want: [][]string{{"fmt", "testing"}},
+	},
+	{
+		name: "four groups",
+		in: `package foo
+
+import "C"
+import (
+	"fmt"
+	"testing"
+
+	"appengine"
+
+	"myproject/mylib1"
+	"myproject/mylib2"
+)
+`,
+		want: [][]string{
+			{"C"},
+			{"fmt", "testing"},
+			{"appengine"},
+			{"myproject/mylib1", "myproject/mylib2"},
+		},
+	},
+	{
+		name: "multiple factored groups",
+		in: `package foo
+
+import (
+	"fmt"
+	"testing"
+
+	"appengine"
+)
+import (
+	"reflect"
+
+	"bytes"
+)
+`,
+		want: [][]string{
+			{"fmt", "testing"},
+			{"appengine"},
+			{"reflect"},
+			{"bytes"},
+		},
+	},
+}
+
+func unquote(s string) string {
+	res, err := strconv.Unquote(s)
+	if err != nil {
+		return "could_not_unquote"
+	}
+	return res
+}
+
+func TestImports(t *testing.T) {
+	fset := token.NewFileSet()
+	for _, test := range importsTests {
+		f, err := parser.ParseFile(fset, "test.go", test.in, 0)
+		if err != nil {
+			t.Errorf("%s: %v", test.name, err)
+			continue
+		}
+		var got [][]string
+		for _, group := range Imports(fset, f) {
+			var b []string
+			for _, spec := range group {
+				b = append(b, unquote(spec.Path.Value))
+			}
+			got = append(got, b)
+		}
+		if !reflect.DeepEqual(got, test.want) {
+			t.Errorf("Imports(%s)=%v, want %v", test.name, got, test.want)
+		}
+	}
+}
+
+var usesImportTests = []struct {
+	name string
+	path string
+	in   string
+	want bool
+}{
+	{
+		name: "no packages",
+		path: "io",
+		in: `package foo
+`,
+		want: false,
+	},
+	{
+		name: "import.1",
+		path: "io",
+		in: `package foo
+
+import "io"
+
+var _ io.Writer
+`,
+		want: true,
+	},
+	{
+		name: "import.2",
+		path: "io",
+		in: `package foo
+
+import "io"
+`,
+		want: false,
+	},
+	{
+		name: "import.3",
+		path: "io",
+		in: `package foo
+
+import "io"
+
+var io = 42
+`,
+		want: false,
+	},
+	{
+		name: "import.4",
+		path: "io",
+		in: `package foo
+
+import i "io"
+
+var _ i.Writer
+`,
+		want: true,
+	},
+	{
+		name: "import.5",
+		path: "io",
+		in: `package foo
+
+import i "io"
+`,
+		want: false,
+	},
+	{
+		name: "import.6",
+		path: "io",
+		in: `package foo
+
+import i "io"
+
+var i = 42
+var io = 42
+`,
+		want: false,
+	},
+	{
+		name: "import.7",
+		path: "encoding/json",
+		in: `package foo
+
+import "encoding/json"
+
+var _ json.Encoder
+`,
+		want: true,
+	},
+	{
+		name: "import.8",
+		path: "encoding/json",
+		in: `package foo
+
+import "encoding/json"
+`,
+		want: false,
+	},
+	{
+		name: "import.9",
+		path: "encoding/json",
+		in: `package foo
+
+import "encoding/json"
+
+var json = 42
+`,
+		want: false,
+	},
+	{
+		name: "import.10",
+		path: "encoding/json",
+		in: `package foo
+
+import j "encoding/json"
+
+var _ j.Encoder
+`,
+		want: true,
+	},
+	{
+		name: "import.11",
+		path: "encoding/json",
+		in: `package foo
+
+import j "encoding/json"
+`,
+		want: false,
+	},
+	{
+		name: "import.12",
+		path: "encoding/json",
+		in: `package foo
+
+import j "encoding/json"
+
+var j = 42
+var json = 42
+`,
+		want: false,
+	},
+	{
+		name: "import.13",
+		path: "io",
+		in: `package foo
+
+import _ "io"
+`,
+		want: true,
+	},
+	{
+		name: "import.14",
+		path: "io",
+		in: `package foo
+
+import . "io"
+`,
+		want: true,
+	},
+}
+
+func TestUsesImport(t *testing.T) {
+	fset := token.NewFileSet()
+	for _, test := range usesImportTests {
+		f, err := parser.ParseFile(fset, "test.go", test.in, 0)
+		if err != nil {
+			t.Errorf("%s: %v", test.name, err)
+			continue
+		}
+		got := UsesImport(f, test.path)
+		if got != test.want {
+			t.Errorf("UsesImport(%s)=%v, want %v", test.name, got, test.want)
+		}
+	}
+}