Add generated file

This PR adds generated files under pkg/client and vendor folder.

vendor/golang.org/x/tools/cmd/guru/whicherrs.go

@@ -0,0 +1,327 @@
+// Copyright 2014 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 main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"sort"
+
+	"golang.org/x/tools/cmd/guru/serial"
+	"golang.org/x/tools/go/ast/astutil"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/pointer"
+	"golang.org/x/tools/go/ssa"
+	"golang.org/x/tools/go/ssa/ssautil"
+)
+
+var builtinErrorType = types.Universe.Lookup("error").Type()
+
+// whicherrs takes an position to an error and tries to find all types, constants
+// and global value which a given error can point to and which can be checked from the
+// scope where the error lives.
+// In short, it returns a list of things that can be checked against in order to handle
+// an error properly.
+//
+// TODO(dmorsing): figure out if fields in errors like *os.PathError.Err
+// can be queried recursively somehow.
+func whicherrs(q *Query) error {
+	lconf := loader.Config{Build: q.Build}
+
+	if err := setPTAScope(&lconf, q.Scope); err != nil {
+		return err
+	}
+
+	// Load/parse/type-check the program.
+	lprog, err := loadWithSoftErrors(&lconf)
+	if err != nil {
+		return err
+	}
+
+	qpos, err := parseQueryPos(lprog, q.Pos, true) // needs exact pos
+	if err != nil {
+		return err
+	}
+
+	prog := ssautil.CreateProgram(lprog, ssa.GlobalDebug)
+
+	ptaConfig, err := setupPTA(prog, lprog, q.PTALog, q.Reflection)
+	if err != nil {
+		return err
+	}
+
+	path, action := findInterestingNode(qpos.info, qpos.path)
+	if action != actionExpr {
+		return fmt.Errorf("whicherrs wants an expression; got %s",
+			astutil.NodeDescription(qpos.path[0]))
+	}
+	var expr ast.Expr
+	var obj types.Object
+	switch n := path[0].(type) {
+	case *ast.ValueSpec:
+		// ambiguous ValueSpec containing multiple names
+		return fmt.Errorf("multiple value specification")
+	case *ast.Ident:
+		obj = qpos.info.ObjectOf(n)
+		expr = n
+	case ast.Expr:
+		expr = n
+	default:
+		return fmt.Errorf("unexpected AST for expr: %T", n)
+	}
+
+	typ := qpos.info.TypeOf(expr)
+	if !types.Identical(typ, builtinErrorType) {
+		return fmt.Errorf("selection is not an expression of type 'error'")
+	}
+	// Determine the ssa.Value for the expression.
+	var value ssa.Value
+	if obj != nil {
+		// def/ref of func/var object
+		value, _, err = ssaValueForIdent(prog, qpos.info, obj, path)
+	} else {
+		value, _, err = ssaValueForExpr(prog, qpos.info, path)
+	}
+	if err != nil {
+		return err // e.g. trivially dead code
+	}
+
+	// Defer SSA construction till after errors are reported.
+	prog.Build()
+
+	globals := findVisibleErrs(prog, qpos)
+	constants := findVisibleConsts(prog, qpos)
+
+	res := &whicherrsResult{
+		qpos:   qpos,
+		errpos: expr.Pos(),
+	}
+
+	// TODO(adonovan): the following code is heavily duplicated
+	// w.r.t.  "pointsto".  Refactor?
+
+	// Find the instruction which initialized the
+	// global error. If more than one instruction has stored to the global
+	// remove the global from the set of values that we want to query.
+	allFuncs := ssautil.AllFunctions(prog)
+	for fn := range allFuncs {
+		for _, b := range fn.Blocks {
+			for _, instr := range b.Instrs {
+				store, ok := instr.(*ssa.Store)
+				if !ok {
+					continue
+				}
+				gval, ok := store.Addr.(*ssa.Global)
+				if !ok {
+					continue
+				}
+				gbl, ok := globals[gval]
+				if !ok {
+					continue
+				}
+				// we already found a store to this global
+				// The normal error define is just one store in the init
+				// so we just remove this global from the set we want to query
+				if gbl != nil {
+					delete(globals, gval)
+				}
+				globals[gval] = store.Val
+			}
+		}
+	}
+
+	ptaConfig.AddQuery(value)
+	for _, v := range globals {
+		ptaConfig.AddQuery(v)
+	}
+
+	ptares := ptrAnalysis(ptaConfig)
+	valueptr := ptares.Queries[value]
+	if valueptr == (pointer.Pointer{}) {
+		return fmt.Errorf("pointer analysis did not find expression (dead code?)")
+	}
+	for g, v := range globals {
+		ptr, ok := ptares.Queries[v]
+		if !ok {
+			continue
+		}
+		if !ptr.MayAlias(valueptr) {
+			continue
+		}
+		res.globals = append(res.globals, g)
+	}
+	pts := valueptr.PointsTo()
+	dedup := make(map[*ssa.NamedConst]bool)
+	for _, label := range pts.Labels() {
+		// These values are either MakeInterfaces or reflect
+		// generated interfaces. For the purposes of this
+		// analysis, we don't care about reflect generated ones
+		makeiface, ok := label.Value().(*ssa.MakeInterface)
+		if !ok {
+			continue
+		}
+		constval, ok := makeiface.X.(*ssa.Const)
+		if !ok {
+			continue
+		}
+		c := constants[*constval]
+		if c != nil && !dedup[c] {
+			dedup[c] = true
+			res.consts = append(res.consts, c)
+		}
+	}
+	concs := pts.DynamicTypes()
+	concs.Iterate(func(conc types.Type, _ interface{}) {
+		// go/types is a bit annoying here.
+		// We want to find all the types that we can
+		// typeswitch or assert to. This means finding out
+		// if the type pointed to can be seen by us.
+		//
+		// For the purposes of this analysis, we care only about
+		// TypeNames of Named or pointer-to-Named types.
+		// We ignore other types (e.g. structs) that implement error.
+		var name *types.TypeName
+		switch t := conc.(type) {
+		case *types.Pointer:
+			named, ok := t.Elem().(*types.Named)
+			if !ok {
+				return
+			}
+			name = named.Obj()
+		case *types.Named:
+			name = t.Obj()
+		default:
+			return
+		}
+		if !isAccessibleFrom(name, qpos.info.Pkg) {
+			return
+		}
+		res.types = append(res.types, &errorType{conc, name})
+	})
+	sort.Sort(membersByPosAndString(res.globals))
+	sort.Sort(membersByPosAndString(res.consts))
+	sort.Sort(sorterrorType(res.types))
+
+	q.Output(lprog.Fset, res)
+	return nil
+}
+
+// findVisibleErrs returns a mapping from each package-level variable of type "error" to nil.
+func findVisibleErrs(prog *ssa.Program, qpos *queryPos) map[*ssa.Global]ssa.Value {
+	globals := make(map[*ssa.Global]ssa.Value)
+	for _, pkg := range prog.AllPackages() {
+		for _, mem := range pkg.Members {
+			gbl, ok := mem.(*ssa.Global)
+			if !ok {
+				continue
+			}
+			gbltype := gbl.Type()
+			// globals are always pointers
+			if !types.Identical(deref(gbltype), builtinErrorType) {
+				continue
+			}
+			if !isAccessibleFrom(gbl.Object(), qpos.info.Pkg) {
+				continue
+			}
+			globals[gbl] = nil
+		}
+	}
+	return globals
+}
+
+// findVisibleConsts returns a mapping from each package-level constant assignable to type "error", to nil.
+func findVisibleConsts(prog *ssa.Program, qpos *queryPos) map[ssa.Const]*ssa.NamedConst {
+	constants := make(map[ssa.Const]*ssa.NamedConst)
+	for _, pkg := range prog.AllPackages() {
+		for _, mem := range pkg.Members {
+			obj, ok := mem.(*ssa.NamedConst)
+			if !ok {
+				continue
+			}
+			consttype := obj.Type()
+			if !types.AssignableTo(consttype, builtinErrorType) {
+				continue
+			}
+			if !isAccessibleFrom(obj.Object(), qpos.info.Pkg) {
+				continue
+			}
+			constants[*obj.Value] = obj
+		}
+	}
+
+	return constants
+}
+
+type membersByPosAndString []ssa.Member
+
+func (a membersByPosAndString) Len() int { return len(a) }
+func (a membersByPosAndString) Less(i, j int) bool {
+	cmp := a[i].Pos() - a[j].Pos()
+	return cmp < 0 || cmp == 0 && a[i].String() < a[j].String()
+}
+func (a membersByPosAndString) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
+
+type sorterrorType []*errorType
+
+func (a sorterrorType) Len() int { return len(a) }
+func (a sorterrorType) Less(i, j int) bool {
+	cmp := a[i].obj.Pos() - a[j].obj.Pos()
+	return cmp < 0 || cmp == 0 && a[i].typ.String() < a[j].typ.String()
+}
+func (a sorterrorType) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
+
+type errorType struct {
+	typ types.Type      // concrete type N or *N that implements error
+	obj *types.TypeName // the named type N
+}
+
+type whicherrsResult struct {
+	qpos    *queryPos
+	errpos  token.Pos
+	globals []ssa.Member
+	consts  []ssa.Member
+	types   []*errorType
+}
+
+func (r *whicherrsResult) PrintPlain(printf printfFunc) {
+	if len(r.globals) > 0 {
+		printf(r.qpos, "this error may point to these globals:")
+		for _, g := range r.globals {
+			printf(g.Pos(), "\t%s", g.RelString(r.qpos.info.Pkg))
+		}
+	}
+	if len(r.consts) > 0 {
+		printf(r.qpos, "this error may contain these constants:")
+		for _, c := range r.consts {
+			printf(c.Pos(), "\t%s", c.RelString(r.qpos.info.Pkg))
+		}
+	}
+	if len(r.types) > 0 {
+		printf(r.qpos, "this error may contain these dynamic types:")
+		for _, t := range r.types {
+			printf(t.obj.Pos(), "\t%s", r.qpos.typeString(t.typ))
+		}
+	}
+}
+
+func (r *whicherrsResult) JSON(fset *token.FileSet) []byte {
+	we := &serial.WhichErrs{}
+	we.ErrPos = fset.Position(r.errpos).String()
+	for _, g := range r.globals {
+		we.Globals = append(we.Globals, fset.Position(g.Pos()).String())
+	}
+	for _, c := range r.consts {
+		we.Constants = append(we.Constants, fset.Position(c.Pos()).String())
+	}
+	for _, t := range r.types {
+		var et serial.WhichErrsType
+		et.Type = r.qpos.typeString(t.typ)
+		et.Position = fset.Position(t.obj.Pos()).String()
+		we.Types = append(we.Types, et)
+	}
+	return toJSON(we)
+}