From 9bc59e6af8481c25e00a732d2bd945b3eac952c1 Mon Sep 17 00:00:00 2001 From: Aaron Craelius Date: Fri, 15 Jul 2022 13:16:35 +0200 Subject: [PATCH] feat(depinject): codegen part 1 (imports & idents) (#12557) ## Description Ref #12556 To make things easier I've starting splitting up #12469 into smaller PRs. This first PR for codegen adds basic infrastructure for: * adding package imports * creating new var names (`*ast.Ident`) without conflicts Other PRs will add the actual codegen functionality. --- ### Author Checklist *All items are required. Please add a note to the item if the item is not applicable and please add links to any relevant follow up issues.* I have... - [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title - [ ] added `!` to the type prefix if API or client breaking change - [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#pr-targeting)) - [ ] provided a link to the relevant issue or specification - [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/main/docs/building-modules) - [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#testing) - [ ] added a changelog entry to `CHANGELOG.md` - [ ] included comments for [documenting Go code](https://blog.golang.org/godoc) - [ ] updated the relevant documentation or specification - [ ] reviewed "Files changed" and left comments if necessary - [ ] confirmed all CI checks have passed ### Reviewers Checklist *All items are required. Please add a note if the item is not applicable and please add your handle next to the items reviewed if you only reviewed selected items.* I have... - [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title - [ ] confirmed `!` in the type prefix if API or client breaking change - [ ] confirmed all author checklist items have been addressed - [ ] reviewed state machine logic - [ ] reviewed API design and naming - [ ] reviewed documentation is accurate - [ ] reviewed tests and test coverage - [ ] manually tested (if applicable) --- depinject/internal/codegen/file.go | 90 +++++++++++++++++++++++ depinject/internal/codegen/func.go | 31 ++++++++ depinject/internal/codegen/ident.go | 29 ++++++++ depinject/internal/codegen/ident_test.go | 48 ++++++++++++ depinject/internal/codegen/import.go | 48 ++++++++++++ depinject/internal/codegen/import_test.go | 60 +++++++++++++++ 6 files changed, 306 insertions(+) create mode 100644 depinject/internal/codegen/file.go create mode 100644 depinject/internal/codegen/func.go create mode 100644 depinject/internal/codegen/ident.go create mode 100644 depinject/internal/codegen/ident_test.go create mode 100644 depinject/internal/codegen/import.go create mode 100644 depinject/internal/codegen/import_test.go diff --git a/depinject/internal/codegen/file.go b/depinject/internal/codegen/file.go new file mode 100644 index 0000000000..dba77becb1 --- /dev/null +++ b/depinject/internal/codegen/file.go @@ -0,0 +1,90 @@ +package codegen + +import ( + "fmt" + "go/ast" + "go/token" + "strconv" +) + +// FileGen is a utility for generating/patching golang file ASTs. +type FileGen struct { + File *ast.File + idents map[string]bool + codegenPkgPath string + pkgImportMap map[string]*importInfo +} + +// NewFileGen creates a new FileGen instance from a file AST with the provided package path. +func NewFileGen(file *ast.File, codegenPkgPath string) (*FileGen, error) { + g := &FileGen{ + File: file, + idents: map[string]bool{}, + codegenPkgPath: codegenPkgPath, + pkgImportMap: map[string]*importInfo{}, + } + + // add all go keywords to reserved idents + for i := token.Token(0); i <= token.TILDE; i++ { + name := i.String() + if token.IsKeyword(name) { + g.idents[name] = true + } + } + + // add all top-level decl idents + for _, decl := range file.Decls { + switch decl := decl.(type) { + case *ast.FuncDecl: + g.idents[decl.Name.Name] = true + case *ast.GenDecl: + for _, spec := range decl.Specs { + switch spec := spec.(type) { + case *ast.TypeSpec: + g.idents[spec.Name.Name] = true + case *ast.ValueSpec: + for _, name := range spec.Names { + g.idents[name.Name] = true + } + } + } + } + } + + for _, spec := range file.Imports { + pkgPath, err := strconv.Unquote(spec.Path.Value) + if err != nil { + return nil, err + } + + var info *importInfo + if spec.Name != nil { + name := spec.Name.Name + if name == "." { + return nil, fmt.Errorf(". package imports are not allowed") + } + + info = &importInfo{importPrefix: name, ImportSpec: spec} + } else { + prefix := defaultPkgPrefix(pkgPath) + info = &importInfo{importPrefix: prefix, ImportSpec: spec} + } + g.pkgImportMap[pkgPath] = info + g.idents[info.importPrefix] = true + } + + return g, nil +} + +// PatchFuncDecl returns a FuncGen instance for the function declaration with the given name or returns nil. +func (g *FileGen) PatchFuncDecl(name string) *FuncGen { + for _, decl := range g.File.Decls { + funcDecl, ok := decl.(*ast.FuncDecl) + if ok { + if funcDecl.Name.Name == name { + return newFuncGen(g, funcDecl) + } + } + } + return nil +} diff --git a/depinject/internal/codegen/func.go b/depinject/internal/codegen/func.go new file mode 100644 index 0000000000..f776d74302 --- /dev/null +++ b/depinject/internal/codegen/func.go @@ -0,0 +1,31 @@ +package codegen + +import ( + "go/ast" +) + +// FuncGen is a utility for generating/patching golang function declaration ASTs. +type FuncGen struct { + *FileGen + Func *ast.FuncDecl +} + +func newFuncGen(fileGen *FileGen, f *ast.FuncDecl) *FuncGen { + g := &FuncGen{FileGen: fileGen, Func: f} + + // reserve param idents + for _, field := range f.Type.Params.List { + for _, name := range field.Names { + g.idents[name.Name] = true + } + } + + // reserve result + for _, field := range f.Type.Results.List { + for _, name := range field.Names { + g.idents[name.Name] = true + } + } + + return g +} diff --git a/depinject/internal/codegen/ident.go b/depinject/internal/codegen/ident.go new file mode 100644 index 0000000000..045678910d --- /dev/null +++ b/depinject/internal/codegen/ident.go @@ -0,0 +1,29 @@ +package codegen + +import ( + "fmt" + "go/ast" +) + +// CreateIdent creates a new ident that doesn't conflict with reserved symbols, +// top-level declarations and other defined idents. Idents are unique across +// the whole file as it is assumed that codegen usually happens on one function +// per file. +func (g *FileGen) CreateIdent(namePrefix string) *ast.Ident { + return ast.NewIdent(g.doCreateIdent(namePrefix)) +} + +func (g *FileGen) doCreateIdent(namePrefix string) string { + v := namePrefix + i := 2 + for { + _, ok := g.idents[v] + if !ok { + g.idents[v] = true + return v + } + + v = fmt.Sprintf("%s%d", namePrefix, i) + i++ + } +} diff --git a/depinject/internal/codegen/ident_test.go b/depinject/internal/codegen/ident_test.go new file mode 100644 index 0000000000..bd7e1bc4f6 --- /dev/null +++ b/depinject/internal/codegen/ident_test.go @@ -0,0 +1,48 @@ +package codegen + +import ( + "go/parser" + "go/token" + "testing" + + "gotest.tools/v3/assert" +) + +func TestReservedIdents(t *testing.T) { + const src = ` +package mypkg + +import "example.com/bar" + +type MyInt int + +var myVar int + +func Build(a, a2 int, b string) (c int, err error) {} +` + file, err := parser.ParseFile(token.NewFileSet(), "", src, 0) + assert.NilError(t, err) + + fileGen, err := NewFileGen(file, "example.com/mypkg") + assert.NilError(t, err) + funcGen := fileGen.PatchFuncDecl("Build") + assert.Assert(t, funcGen != nil) + + // go keywords get a suffix + assert.Equal(t, "type2", funcGen.CreateIdent("type").Name) + assert.Equal(t, "package2", funcGen.CreateIdent("package").Name) + assert.Equal(t, "goto2", funcGen.CreateIdent("goto").Name) + + // import name prefixes get suffixes + assert.Equal(t, "bar2", funcGen.CreateIdent("bar").Name) + + // top-level decl names get prefixes + assert.Equal(t, "MyInt2", funcGen.CreateIdent("MyInt").Name) + assert.Equal(t, "myVar2", funcGen.CreateIdent("myVar").Name) + + // param and result names get suffixes at func level + assert.Equal(t, "a3", funcGen.CreateIdent("a").Name) + assert.Equal(t, "b2", funcGen.CreateIdent("b").Name) + assert.Equal(t, "c2", funcGen.CreateIdent("c").Name) + assert.Equal(t, "err2", funcGen.CreateIdent("err").Name) +} diff --git a/depinject/internal/codegen/import.go b/depinject/internal/codegen/import.go new file mode 100644 index 0000000000..171f2d462a --- /dev/null +++ b/depinject/internal/codegen/import.go @@ -0,0 +1,48 @@ +package codegen + +import ( + "fmt" + "go/ast" + "go/token" + "strings" +) + +type importInfo struct { + *ast.ImportSpec + importPrefix string +} + +// AddOrGetImport adds a new import for the provided pkgPath (if needed) and +// returns the unique import prefix for that path. +func (g *FileGen) AddOrGetImport(pkgPath string) (importPrefix string) { + if pkgPath == "" || pkgPath == g.codegenPkgPath { + return "" + } + + if i, ok := g.pkgImportMap[pkgPath]; ok { + return i.importPrefix + } + + imp := &ast.ImportSpec{ + Path: &ast.BasicLit{Kind: token.STRING, Value: fmt.Sprintf("%q", pkgPath)}, + } + + defaultPrefix := defaultPkgPrefix(pkgPath) + importPrefix = g.doCreateIdent(defaultPrefix) + + if importPrefix != defaultPrefix { + imp.Name = ast.NewIdent(importPrefix) + } + g.File.Imports = append(g.File.Imports, imp) + g.pkgImportMap[pkgPath] = &importInfo{ + ImportSpec: imp, + importPrefix: importPrefix, + } + g.idents[importPrefix] = true + return importPrefix +} + +func defaultPkgPrefix(pkgPath string) string { + pkgParts := strings.Split(pkgPath, "/") + return pkgParts[len(pkgParts)-1] +} diff --git a/depinject/internal/codegen/import_test.go b/depinject/internal/codegen/import_test.go new file mode 100644 index 0000000000..4665ed9ffb --- /dev/null +++ b/depinject/internal/codegen/import_test.go @@ -0,0 +1,60 @@ +package codegen + +import ( + "go/parser" + "go/token" + "testing" + + "gotest.tools/v3/assert" +) + +func TestImport(t *testing.T) { + const badFileSrc = ` +package mypkg + +import . "example.com/foo" +` + + badFile, err := parser.ParseFile(token.NewFileSet(), "", badFileSrc, 0) + assert.NilError(t, err) + + _, err = NewFileGen(badFile, "example.com/mypkg") + assert.ErrorContains(t, err, ".") + + const goodFileSrc = ` +package mypkg + +import "example.com/foo" +import abc "example.com/bar" +` + + goodFile, err := parser.ParseFile(token.NewFileSet(), "", goodFileSrc, 0) + assert.NilError(t, err) + assert.Equal(t, 2, len(goodFile.Imports)) + + fgen, err := NewFileGen(goodFile, "example.com/mypkg") + assert.NilError(t, err) + + // self import is "" + assert.Equal(t, "", fgen.AddOrGetImport("example.com/mypkg")) + + // bar import is abc, no new import was added + assert.Equal(t, "abc", fgen.AddOrGetImport("example.com/bar")) + assert.Equal(t, 2, len(goodFile.Imports)) + + // foo import is foo, no new import is added + assert.Equal(t, "foo", fgen.AddOrGetImport("example.com/foo")) + assert.Equal(t, 2, len(goodFile.Imports)) + + // baz import is baz, a new import is added + assert.Equal(t, "baz", fgen.AddOrGetImport("example.com/baz")) + assert.Equal(t, 3, len(goodFile.Imports)) + + // another foo import is foo2, a new import is added + assert.Equal(t, "foo2", fgen.AddOrGetImport("example2.com/foo")) + assert.Equal(t, 4, len(goodFile.Imports)) + + // another baz import is baz2, a new import is added + assert.Equal(t, "baz2", fgen.AddOrGetImport("example.com/foo/baz")) + assert.Equal(t, 5, len(goodFile.Imports)) +}