golang.org/x/tools v0.1.5

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify pkg:golang/golang.org/x/tools@v0.1.5
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/tools@v0.1.5

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:c0216acafb7b40d6388c5bb6b85ec2647cb14a5a3fc5ac91062cf8de2c6b82cc","contract":["astutil.UsesImport reports whether an import path is referenced in a parsed Go AST","astutil.AddImport inserts a new import spec into the AST and returns false on duplicate imports","astutil.DeleteImport removes an existing import spec from the AST","astutil.Apply traverses AST nodes with a cursor callback","imports.Process formats Go source code while adding missing imports and removing unused imports"],"goal":"verify pkg:golang/golang.org/x/tools@v0.1.5","kind":"HOW","packages":["pkg:golang/golang.org/x/tools@v0.1.5"],"schemaVersion":1},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/golang.org/x/tools@v0.1.5"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/tools@v0.1.5","verifierAdapter":"golang@1"}

module sample

go 1.22

require golang.org/x/tools v0.1.5

require (
	golang.org/x/mod v0.4.2 // indirect
	golang.org/x/sys v0.0.0-20210510120138-977fb7262007 // indirect
	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
)

golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
golang.org/x/mod v0.4.2 h1:Gz96sIWK3OalVv/I/qNygP42zyoKp3xptRVCWRFEBvo=
golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/sys v0.0.0-20210510120138-977fb7262007 h1:gG67DSER+11cZvqIMb8S8bt0vZtiN6xWYARwirrOSfE=
golang.org/x/sys v0.0.0-20210510120138-977fb7262007/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
golang.org/x/tools v0.1.5 h1:ouewzE6p+/VEB31YYnTbEJdi8pFqKp4P4n85vwo3DHA=
golang.org/x/tools v0.1.5/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

{
  "schemaVersion": 1,
  "goal": "verify pkg:golang/golang.org/x/tools@v0.1.5",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/tools@v0.1.5"
  ]
}

package main

import (
	"bytes"
	"fmt"
	"go/ast"
	"go/format"
	"go/parser"
	"go/token"
	"os"
	"strings"

	"golang.org/x/tools/go/ast/astutil"
	"golang.org/x/tools/imports"
)

func main() {
	if err := verifyContract(); err != nil {
		fmt.Fprintf(os.Stderr, "contract failed: %v\n", err)
		os.Exit(1)
	}
}

func verifyContract() error {
	fset := token.NewFileSet()
	src := `package example

import "os"

func Greet(name string) string {
	_ = os.Args
	return name
}
`
	file, err := parser.ParseFile(fset, "example.go", src, parser.ParseComments)
	if err != nil {
		return fmt.Errorf("parse file: %w", err)
	}

	// 1. astutil.UsesImport reports whether an import path is referenced in the AST
	if !astutil.UsesImport(file, "os") {
		return fmt.Errorf("expected UsesImport(os) to be true")
	}
	if astutil.UsesImport(file, "fmt") {
		return fmt.Errorf("expected UsesImport(fmt) to be false before adding")
	}

	// 2. astutil.AddImport inserts a new import spec and returns true when added
	if !astutil.AddImport(fset, file, "strings") {
		return fmt.Errorf("expected AddImport(strings) to return true")
	}
	if astutil.AddImport(fset, file, "strings") {
		return fmt.Errorf("expected duplicate AddImport(strings) to return false")
	}

	// 3. astutil.DeleteImport removes an existing import spec from the AST
	if !astutil.DeleteImport(fset, file, "strings") {
		return fmt.Errorf("expected DeleteImport(strings) to return true")
	}

	// 4. astutil.Apply traverses the AST and allows node inspection and replacement
	var identCount int
	astutil.Apply(file, func(c *astutil.Cursor) bool {
		if _, ok := c.Node().(*ast.Ident); ok {
			identCount++
		}
		return true
	}, nil)
	if identCount == 0 {
		return fmt.Errorf("expected astutil.Apply to visit identifiers")
	}

	var buf bytes.Buffer
	if err := format.Node(&buf, fset, file); err != nil {
		return fmt.Errorf("format node: %w", err)
	}

	// 5. imports.Process formats source code and resolves missing and unused imports
	unformatted := []byte("package example\nimport \"os\"\nfunc Calc() string { return fmt.Sprintf(\"%d\", 42) }\n")
	processed, err := imports.Process("calc.go", unformatted, nil)
	if err != nil {
		return fmt.Errorf("imports.Process failed: %w", err)
	}
	out := string(processed)
	if !strings.Contains(out, `"fmt"`) {
		return fmt.Errorf("expected imports.Process to add fmt import, got:\n%s", out)
	}
	if strings.Contains(out, `"os"`) {
		return fmt.Errorf("expected imports.Process to remove unused os import, got:\n%s", out)
	}

	return nil
}