On of cases for #260: fix crash in staticcheck

1. Fix crash if deps of analyzed packages weren't compiled.
2. Print deps typechecking errors
3. Fix all issues filtering because of empty go env GOCACHE for go < 1.10

pkg/golinters/megacheck.go

@@ -17,6 +17,7 @@ import (
 
 	"github.com/golangci/golangci-lint/pkg/fsutils"
 	"github.com/golangci/golangci-lint/pkg/lint/linter"
+	libpackages "github.com/golangci/golangci-lint/pkg/packages"
 	"github.com/golangci/golangci-lint/pkg/result"
 )
 
@@ -87,7 +88,7 @@ func (m Megacheck) Run(ctx context.Context, lintCtx *linter.Context) ([]result.I
 		var errors []packages.Error
 		for _, p := range lintCtx.NotCompilingPackages {
 			errPkgs = append(errPkgs, p.String())
-			errors = append(errors, p.Errors...)
+			errors = append(errors, libpackages.ExtractErrors(p)...)
 		}
 
 		warnText := fmt.Sprintf("Can't run megacheck because of compilation errors in packages %s",

pkg/golinters/typecheck.go

@@ -11,6 +11,7 @@ import (
 	"golang.org/x/tools/go/packages"
 
 	"github.com/golangci/golangci-lint/pkg/lint/linter"
+	libpackages "github.com/golangci/golangci-lint/pkg/packages"
 	"github.com/golangci/golangci-lint/pkg/result"
 )
 
@@ -59,7 +60,8 @@ func (lint TypeCheck) parseError(srcErr packages.Error) (*result.Issue, error) {
 func (lint TypeCheck) Run(ctx context.Context, lintCtx *linter.Context) ([]result.Issue, error) {
 	var res []result.Issue
 	for _, pkg := range lintCtx.NotCompilingPackages {
-		for _, err := range pkg.Errors {
+		errors := libpackages.ExtractErrors(pkg)
+		for _, err := range errors {
 			i, perr := lint.parseError(err)
 			if perr != nil {
 				res = append(res, result.Issue{

pkg/lint/load.go

@@ -23,6 +23,7 @@ import (
 	"github.com/golangci/golangci-lint/pkg/lint/astcache"
 	"github.com/golangci/golangci-lint/pkg/lint/linter"
 	"github.com/golangci/golangci-lint/pkg/logutils"
+	libpackages "github.com/golangci/golangci-lint/pkg/packages"
 )
 
 type ContextLoader struct {
@@ -88,7 +89,7 @@ func shouldSkipPkg(pkg *packages.Package) bool {
 func (cl ContextLoader) makeFakeLoaderProgram(pkgs []*packages.Package) *loader.Program {
 	var createdPkgs []*loader.PackageInfo
 	for _, pkg := range pkgs {
-		if len(pkg.Errors) != 0 {
+		if pkg.IllTyped {
 			// some linters crash on packages with errors,
 			// skip them and warn about them in another place
 			continue
@@ -104,7 +105,7 @@ func (cl ContextLoader) makeFakeLoaderProgram(pkgs []*packages.Package) *loader.
 		allPkgs[pkg.Pkg] = pkg
 	}
 	for _, pkg := range pkgs {
-		if len(pkg.Errors) != 0 {
+		if pkg.IllTyped {
 			// some linters crash on packages with errors,
 			// skip them and warn about them in another place
 			continue
@@ -346,8 +347,8 @@ func (cl ContextLoader) Load(ctx context.Context, linters []linter.Config) (*lin
 		saveNotCompilingPackages(ret)
 	} else {
 		for _, pkg := range pkgs {
-			if len(pkg.Errors) != 0 {
+			if pkg.IllTyped {
-				cl.log.Infof("Pkg %s errors: %v", pkg.ID, pkg.Errors)
+				cl.log.Infof("Pkg %s errors: %v", pkg.ID, libpackages.ExtractErrors(pkg))
 			}
 		}
 	}
@@ -360,7 +361,7 @@ func (cl ContextLoader) Load(ctx context.Context, linters []linter.Config) (*lin
 // which can work with them.
 func saveNotCompilingPackages(lintCtx *linter.Context) {
 	for _, pkg := range lintCtx.Packages {
-		if len(pkg.Errors) != 0 {
+		if pkg.IllTyped {
 			lintCtx.NotCompilingPackages = append(lintCtx.NotCompilingPackages, pkg)
 		}
 	}

pkg/packages/util.go

@@ -0,0 +1,51 @@
+package packages
+
+import (
+	"fmt"
+
+	"golang.org/x/tools/go/packages"
+)
+
+func ExtractErrors(pkg *packages.Package) []packages.Error {
+	errors := extractErrorsImpl(pkg)
+	if len(errors) == 0 {
+		return errors
+	}
+
+	seenErrors := map[string]bool{}
+	var uniqErrors []packages.Error
+	for _, err := range errors {
+		if seenErrors[err.Msg] {
+			continue
+		}
+		seenErrors[err.Msg] = true
+		uniqErrors = append(uniqErrors, err)
+	}
+
+	if len(pkg.Errors) == 0 && len(pkg.GoFiles) != 0 {
+		// erorrs were extracted from deps and have at leat one file in package
+		for i := range uniqErrors {
+			// change pos to local file to properly process it by processors (properly read line etc)
+			uniqErrors[i].Msg = fmt.Sprintf("%s: %s", uniqErrors[i].Pos, uniqErrors[i].Msg)
+			uniqErrors[i].Pos = fmt.Sprintf("%s:1", pkg.GoFiles[0])
+		}
+	}
+
+	return uniqErrors
+}
+
+func extractErrorsImpl(pkg *packages.Package) []packages.Error {
+	if len(pkg.Errors) != 0 {
+		return pkg.Errors
+	}
+
+	var errors []packages.Error
+	for _, iPkg := range pkg.Imports {
+		iPkgErrors := extractErrorsImpl(iPkg)
+		if iPkgErrors != nil {
+			errors = append(errors, iPkgErrors...)
+		}
+	}
+
+	return errors
+}

pkg/result/processors/cgo.go

@@ -42,7 +42,7 @@ func (p Cgo) Process(issues []result.Issue) ([]result.Issue, error) {
 			issueFilePath = absPath
 		}
 
-		if strings.HasPrefix(issueFilePath, p.goCacheDir) {
+		if p.goCacheDir != "" && strings.HasPrefix(issueFilePath, p.goCacheDir) {
 			return false, nil
 		}
 

pkg/result/processors/skip_dirs.go

@@ -52,7 +52,6 @@ func NewSkipDirs(patterns []string, log logutils.Log, runArgs []string) (*SkipDi
 		sortedAbsArgs = append(sortedAbsArgs, absArg)
 	}
 	sort.Sort(sortedByLenStrings(sortedAbsArgs))
-	log.Infof("sorted abs args: %s", sortedAbsArgs)
 
 	return &SkipDirs{
 		patterns:      patternsRe,