Giant blob of minor changes

[dotfiles/.git] / .config / coc / extensions / coc-go-data / tools / pkg / mod / golang.org / x / tools@v0.0.0-20201105173854-bc9fc8d8c4bc / go / analysis / passes / assign / assign.go

diff --git a/.config/coc/extensions/coc-go-data/tools/pkg/mod/golang.org/x/tools@v0.0.0-20201105173854-bc9fc8d8c4bc/go/analysis/passes/assign/assign.go b/.config/coc/extensions/coc-go-data/tools/pkg/mod/golang.org/x/tools@v0.0.0-20201105173854-bc9fc8d8c4bc/go/analysis/passes/assign/assign.go
new file mode 100644 (file)
index 0000000..3586638
--- /dev/null
+++ b/.config/coc/extensions/coc-go-data/tools/pkg/mod/golang.org/x/tools@v0.0.0-20201105173854-bc9fc8d8c4bc/go/analysis/passes/assign/assign.go
@@ -0,0 +1,76 @@
+// 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 assign defines an Analyzer that detects useless assignments.
+package assign
+
+// TODO(adonovan): check also for assignments to struct fields inside
+// methods that are on T instead of *T.
+
+import (
+       "fmt"
+       "go/ast"
+       "go/token"
+       "reflect"
+
+       "golang.org/x/tools/go/analysis"
+       "golang.org/x/tools/go/analysis/passes/inspect"
+       "golang.org/x/tools/go/analysis/passes/internal/analysisutil"
+       "golang.org/x/tools/go/ast/inspector"
+)
+
+const Doc = `check for useless assignments
+
+This checker reports assignments of the form x = x or a[i] = a[i].
+These are almost always useless, and even when they aren't they are
+usually a mistake.`
+
+var Analyzer = &analysis.Analyzer{
+       Name:     "assign",
+       Doc:      Doc,
+       Requires: []*analysis.Analyzer{inspect.Analyzer},
+       Run:      run,
+}
+
+func run(pass *analysis.Pass) (interface{}, error) {
+       inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
+
+       nodeFilter := []ast.Node{
+               (*ast.AssignStmt)(nil),
+       }
+       inspect.Preorder(nodeFilter, func(n ast.Node) {
+               stmt := n.(*ast.AssignStmt)
+               if stmt.Tok != token.ASSIGN {
+                       return // ignore :=
+               }
+               if len(stmt.Lhs) != len(stmt.Rhs) {
+                       // If LHS and RHS have different cardinality, they can't be the same.
+                       return
+               }
+               for i, lhs := range stmt.Lhs {
+                       rhs := stmt.Rhs[i]
+                       if analysisutil.HasSideEffects(pass.TypesInfo, lhs) ||
+                               analysisutil.HasSideEffects(pass.TypesInfo, rhs) {
+                               continue // expressions may not be equal
+                       }
+                       if reflect.TypeOf(lhs) != reflect.TypeOf(rhs) {
+                               continue // short-circuit the heavy-weight gofmt check
+                       }
+                       le := analysisutil.Format(pass.Fset, lhs)
+                       re := analysisutil.Format(pass.Fset, rhs)
+                       if le == re {
+                               pass.Report(analysis.Diagnostic{
+                                       Pos: stmt.Pos(), Message: fmt.Sprintf("self-assignment of %s to %s", re, le),
+                                       SuggestedFixes: []analysis.SuggestedFix{
+                                               {Message: "Remove", TextEdits: []analysis.TextEdit{
+                                                       {Pos: stmt.Pos(), End: stmt.End(), NewText: []byte{}},
+                                               }},
+                                       },
+                               })
+                       }
+               }
+       })
+
+       return nil, nil
+}