snapshot of https://github.com/mattermost/mattermost.git (master, 2026-09-16; blobs > 131072B omitted)

tools/mattermost-govet/pointerToSlice/pointerToSlice.go

@@ -0,0 +1,89 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package pointerToSlice
+
+import (
+	"go/ast"
+	"strings"
+
+	"golang.org/x/tools/go/analysis"
+)
+
+var (
+	Analyzer = &analysis.Analyzer{
+		Name: "pointerToSlice",
+		Doc:  "check for usage of pointer to slice in function definitions",
+		Run:  run,
+	}
+	ignoreFilesPattern string
+)
+
+func init() {
+	Analyzer.Flags.StringVar(&ignoreFilesPattern, "ignore", "", "Comma separated list of files to ignore")
+}
+
+func run(pass *analysis.Pass) (interface{}, error) {
+	var ignoreFiles []string
+	if ignoreFilesPattern != "" {
+		ignoreFiles = strings.Split(ignoreFilesPattern, ",")
+	}
+
+	checkNode := func(expr ast.Expr) {
+		sexpr, ok := expr.(*ast.StarExpr)
+		if !ok {
+			return
+		}
+		if _, ok := sexpr.X.(*ast.ArrayType); ok {
+			pass.Reportf(sexpr.Pos(), "use of pointer to slice in function definition")
+			return
+		}
+		if tv, ok := pass.TypesInfo.Types[sexpr.X]; ok {
+			if strings.HasPrefix(tv.Type.String(), "[]") || strings.HasPrefix(tv.Type.Underlying().String(), "[]") {
+				pass.Reportf(sexpr.Pos(), "use of pointer to slice in function definition")
+				return
+			}
+		}
+	}
+
+	for _, file := range pass.Files {
+		ast.Inspect(file, func(node ast.Node) bool {
+			if node != nil {
+				f := pass.Fset.File(node.Pos())
+				if isIgnore(f.Name(), ignoreFiles) {
+					return false
+				}
+			}
+
+			f, ok := node.(*ast.FuncDecl)
+			if !ok || f.Type == nil {
+				return true
+			}
+
+			if params := f.Type.Params; params != nil {
+				for _, p := range params.List {
+					checkNode(p.Type)
+				}
+			}
+
+			if results := f.Type.Results; results != nil {
+				for _, r := range results.List {
+					checkNode(r.Type)
+				}
+			}
+
+			return true
+		})
+	}
+
+	return nil, nil
+}
+
+func isIgnore(file string, ignoreFiles []string) bool {
+	for _, f := range ignoreFiles {
+		if strings.HasSuffix(file, f) {
+			return true
+		}
+	}
+	return false
+}

tools/mattermost-govet/pointerToSlice/pointerToSlice_test.go

@@ -0,0 +1,15 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package pointerToSlice
+
+import (
+	"testing"
+
+	"golang.org/x/tools/go/analysis/analysistest"
+)
+
+func Test(t *testing.T) {
+	testdata := analysistest.TestData()
+	analysistest.Run(t, testdata, Analyzer, "model", "app")
+}

tools/mattermost-govet/pointerToSlice/testdata/src/app/app.go

@@ -0,0 +1,9 @@
+package app
+
+import "model"
+
+func ListParamNotValid(list *model.StringList) {} // want `use of pointer to slice in function definition`
+func ListParamValid(list model.StringList)     {}
+
+func ListReturnNotValid() (list *model.StringList) { return nil } // want `use of pointer to slice in function definition`
+func ListReturnValid() (list model.StringList)     { return nil }

tools/mattermost-govet/pointerToSlice/testdata/src/model/model.go

@@ -0,0 +1,11 @@
+package model
+
+type StringList []string
+type IntList []int
+
+func ValidFuncDirect(a int, b []string) []int            { return nil }
+func ValidFuncIndirect(a int, b StringList) IntList      { return nil }
+func InvalidReturnDirect(a int, b StringList) *[]int     { return nil } // want `use of pointer to slice in function definition`
+func InvalidReturnIndirect(a int, b StringList) *IntList { return nil } // want `use of pointer to slice in function definition`
+func InvalidParamDirect(a *[]string, b int)              {}             // want `use of pointer to slice in function definition`
+func InvalidParamIndirect(a int, b *StringList)          {}             // want `use of pointer to slice in function definition`