go.mod: update golangci-lint to v1.37

2 files changed, 288 insertions, 0 deletions

diff --git a/vendor/github.com/alexkohler/prealloc/LICENSE b/vendor/github.com/alexkohler/prealloc/LICENSE
new file mode 100644
index 000000000..9310fbcff
--- /dev/null
+++ b/vendor/github.com/alexkohler/prealloc/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2017 Alex Kohler
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/vendor/github.com/alexkohler/prealloc/pkg/prealloc.go b/vendor/github.com/alexkohler/prealloc/pkg/prealloc.go
new file mode 100644
index 000000000..72d8b95f7
--- /dev/null
+++ b/vendor/github.com/alexkohler/prealloc/pkg/prealloc.go
@@ -0,0 +1,267 @@
+package pkg
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+)
+
+type sliceDeclaration struct {
+	name string
+	// sType string
+	genD *ast.GenDecl
+}
+
+type returnsVisitor struct {
+	// flags
+	simple            bool
+	includeRangeLoops bool
+	includeForLoops   bool
+	// visitor fields
+	sliceDeclarations   []*sliceDeclaration
+	preallocHints       []Hint
+	returnsInsideOfLoop bool
+	arrayTypes          []string
+}
+
+func Check(files []*ast.File, simple, includeRangeLoops, includeForLoops bool) []Hint {
+	hints := []Hint{}
+	for _, f := range files {
+		retVis := &returnsVisitor{
+			simple:            simple,
+			includeRangeLoops: includeRangeLoops,
+			includeForLoops:   includeForLoops,
+		}
+		ast.Walk(retVis, f)
+		// if simple is true, then we actually have to check if we had returns
+		// inside of our loop. Otherwise, we can just report all messages.
+		if !retVis.simple || !retVis.returnsInsideOfLoop {
+			hints = append(hints, retVis.preallocHints...)
+		}
+	}
+
+	return hints
+}
+
+func contains(slice []string, item string) bool {
+	for _, s := range slice {
+		if s == item {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (v *returnsVisitor) Visit(node ast.Node) ast.Visitor {
+
+	v.sliceDeclarations = nil
+	v.returnsInsideOfLoop = false
+
+	switch n := node.(type) {
+	case *ast.TypeSpec:
+		if _, ok := n.Type.(*ast.ArrayType); ok {
+			if n.Name != nil {
+				v.arrayTypes = append(v.arrayTypes, n.Name.Name)
+			}
+		}
+	case *ast.FuncDecl:
+		if n.Body != nil {
+			for _, stmt := range n.Body.List {
+				switch s := stmt.(type) {
+				// Find non pre-allocated slices
+				case *ast.DeclStmt:
+					genD, ok := s.Decl.(*ast.GenDecl)
+					if !ok {
+						continue
+					}
+					if genD.Tok == token.TYPE {
+						for _, spec := range genD.Specs {
+							tSpec, ok := spec.(*ast.TypeSpec)
+							if !ok {
+								continue
+							}
+
+							if _, ok := tSpec.Type.(*ast.ArrayType); ok {
+								if tSpec.Name != nil {
+									v.arrayTypes = append(v.arrayTypes, tSpec.Name.Name)
+								}
+							}
+						}
+					} else if genD.Tok == token.VAR {
+						for _, spec := range genD.Specs {
+							vSpec, ok := spec.(*ast.ValueSpec)
+							if !ok {
+								continue
+							}
+							var isArrType bool
+							switch val := vSpec.Type.(type) {
+							case *ast.ArrayType:
+								isArrType = true
+							case *ast.Ident:
+								isArrType = contains(v.arrayTypes, val.Name)
+							}
+							if isArrType {
+								if vSpec.Names != nil {
+									/*atID, ok := arrayType.Elt.(*ast.Ident)
+									if !ok {
+										continue
+									}*/
+
+									// We should handle multiple slices declared on same line e.g. var mySlice1, mySlice2 []uint32
+									for _, vName := range vSpec.Names {
+										v.sliceDeclarations = append(v.sliceDeclarations, &sliceDeclaration{name: vName.Name /*sType: atID.Name,*/, genD: genD})
+									}
+								}
+							}
+						}
+					}
+
+				case *ast.RangeStmt:
+					if v.includeRangeLoops {
+						if len(v.sliceDeclarations) == 0 {
+							continue
+						}
+						// Check the value being ranged over and ensure it's not a channel (we cannot offer any recommendations on channel ranges).
+						rangeIdent, ok := s.X.(*ast.Ident)
+						if ok && rangeIdent.Obj != nil {
+							valueSpec, ok := rangeIdent.Obj.Decl.(*ast.ValueSpec)
+							if ok {
+								if _, rangeTargetIsChannel := valueSpec.Type.(*ast.ChanType); rangeTargetIsChannel {
+									continue
+								}
+							}
+						}
+						if s.Body != nil {
+							v.handleLoops(s.Body)
+						}
+					}
+
+				case *ast.ForStmt:
+					if v.includeForLoops {
+						if len(v.sliceDeclarations) == 0 {
+							continue
+						}
+						if s.Body != nil {
+							v.handleLoops(s.Body)
+						}
+					}
+
+				default:
+				}
+			}
+		}
+	}
+	return v
+}
+
+// handleLoops is a helper function to share the logic required for both *ast.RangeLoops and *ast.ForLoops
+func (v *returnsVisitor) handleLoops(blockStmt *ast.BlockStmt) {
+
+	for _, stmt := range blockStmt.List {
+		switch bodyStmt := stmt.(type) {
+		case *ast.AssignStmt:
+			asgnStmt := bodyStmt
+			for index, expr := range asgnStmt.Rhs {
+				if index >= len(asgnStmt.Lhs) {
+					continue
+				}
+
+				lhsIdent, ok := asgnStmt.Lhs[index].(*ast.Ident)
+				if !ok {
+					continue
+				}
+
+				callExpr, ok := expr.(*ast.CallExpr)
+				if !ok {
+					continue
+				}
+
+				rhsFuncIdent, ok := callExpr.Fun.(*ast.Ident)
+				if !ok {
+					continue
+				}
+
+				if rhsFuncIdent.Name != "append" {
+					continue
+				}
+
+				// e.g., `x = append(x)`
+				// Pointless, but pre-allocation will not help.
+				if len(callExpr.Args) < 2 {
+					continue
+				}
+
+				rhsIdent, ok := callExpr.Args[0].(*ast.Ident)
+				if !ok {
+					continue
+				}
+
+				// e.g., `x = append(y, a)`
+				// This is weird (and maybe a logic error),
+				// but we cannot recommend pre-allocation.
+				if lhsIdent.Name != rhsIdent.Name {
+					continue
+				}
+
+				// e.g., `x = append(x, y...)`
+				// we should ignore this. Pre-allocating in this case
+				// is confusing, and is not possible in general.
+				if callExpr.Ellipsis.IsValid() {
+					continue
+				}
+
+				for _, sliceDecl := range v.sliceDeclarations {
+					if sliceDecl.name == lhsIdent.Name {
+						// This is a potential mark, we just need to make sure there are no returns/continues in the
+						// range loop.
+						// now we just need to grab whatever we're ranging over
+						/*sxIdent, ok := s.X.(*ast.Ident)
+						if !ok {
+							continue
+						}*/
+
+						v.preallocHints = append(v.preallocHints, Hint{
+							Pos:               sliceDecl.genD.Pos(),
+							DeclaredSliceName: sliceDecl.name,
+						})
+					}
+				}
+			}
+		case *ast.IfStmt:
+			ifStmt := bodyStmt
+			if ifStmt.Body != nil {
+				for _, ifBodyStmt := range ifStmt.Body.List {
+					// TODO should probably handle embedded ifs here
+					switch /*ift :=*/ ifBodyStmt.(type) {
+					case *ast.BranchStmt, *ast.ReturnStmt:
+						v.returnsInsideOfLoop = true
+					default:
+					}
+				}
+			}
+
+		default:
+
+		}
+	}
+
+}
+
+// Hint stores the information about an occurrence of a slice that could be
+// preallocated.
+type Hint struct {
+	Pos               token.Pos
+	DeclaredSliceName string
+}
+
+func (h Hint) String() string {
+	return fmt.Sprintf("%v: Consider preallocating %v", h.Pos, h.DeclaredSliceName)
+}
+
+func (h Hint) StringFromFS(f *token.FileSet) string {
+	file := f.File(h.Pos)
+	lineNumber := file.Position(h.Pos).Line
+
+	return fmt.Sprintf("%v:%v Consider preallocating %v", file.Name(), lineNumber, h.DeclaredSliceName)
+}