Replace config.IsTestEnvironment with a configuration

config/config.go

@@ -27,6 +27,8 @@ import (
 
 // Config is the struct that stores the user-configurable options for NilAway.
 type Config struct {
+	// PrettyPrint indicates whether the error messages should be pretty printed.
+	PrettyPrint bool
 	// includePkgs is the list of packages to analyze.
 	includePkgs []string
 	// excludePkgs is the list of packages to exclude from analysis. Exclude list takes
@@ -111,6 +113,8 @@ var Analyzer = &analysis.Analyzer{
 }
 
 const (
+	// PrettyPrintFlag is the flag for pretty printing the error messages.
+	PrettyPrintFlag = "pretty-print"
 	// IncludePkgsFlag is the flag name for include package prefixes.
 	IncludePkgsFlag = "include-pkgs"
 	// ExcludePkgsFlag is the flag name for exclude package prefixes.
@@ -125,6 +129,7 @@ func newFlagSet() flag.FlagSet {
 
 	// We do not keep the returned pointer to the flags because we will not use them directly here.
 	// Instead, we will use the flags through the analyzer's Flags field later.
+	_ = fs.Bool(PrettyPrintFlag, true, "Pretty print the error messages")
 	_ = fs.String(IncludePkgsFlag, "", "Comma-separated list of packages to analyze")
 	_ = fs.String(ExcludePkgsFlag, "", "Comma-separated list of packages to exclude from analysis")
 	_ = fs.String(ExcludeFileDocStringsFlag, "", "Comma-separated list of docstrings to exclude from analysis")
@@ -135,12 +140,16 @@ func newFlagSet() flag.FlagSet {
 func run(pass *analysis.Pass) (any, error) {
 	// Set up default values for the config.
 	conf := &Config{
+		PrettyPrint: true,
 		// If the user does not provide an include list, we give an empty package prefix to catch
 		// all packages.
 		includePkgs: []string{""},
 	}
 
 	// Override default values if the user provides flags.
+	if prettyPrint, ok := pass.Analyzer.Flags.Lookup(PrettyPrintFlag).Value.(flag.Getter).Get().(bool); ok {
+		conf.PrettyPrint = prettyPrint
+	}
 	if include, ok := pass.Analyzer.Flags.Lookup(IncludePkgsFlag).Value.(flag.Getter).Get().(string); ok && include != "" {
 		conf.includePkgs = strings.Split(include, ",")
 	}

config/const.go

@@ -7,10 +7,6 @@ import (
 
 // This file hosts non-user-configurable parameters --- these are for development and testing purposes only.
 
-// IsTestEnvironment is a global flag that should be to set true if running the test suite, false otherwise. This flag is used
-// to disable the pretty printing used in error reporting.
-var IsTestEnvironment = false
-
 // StableRoundLimit is the number of rounds in backpropagation algorithm after which, if there is no change
 // in the collected triggers, the algorithm halts. It is possible to carefully craft known false negative for any value
 // of StableRoundLimit (check test loopflow.go/longRotNilLoop). Setting this value too low may result in false negatives

nilaway.go

@@ -33,15 +33,15 @@ var Analyzer = &analysis.Analyzer{
 	Doc:       _doc,
 	Run:       run,
 	FactTypes: []analysis.Fact{},
-	Requires:  []*analysis.Analyzer{accumulation.Analyzer},
+	Requires:  []*analysis.Analyzer{config.Analyzer, accumulation.Analyzer},
 }
 
 // nilable(result 0)
 func run(pass *analysis.Pass) (interface{}, error) {
+	conf := pass.ResultOf[config.Analyzer].(*config.Config)
 	deferredErrors := pass.ResultOf[accumulation.Analyzer].([]analysis.Diagnostic)
 	for _, e := range deferredErrors {
-		// Pretty print the error messages in console when not in test environments.
-		if !config.IsTestEnvironment {
+		if conf.PrettyPrint {
 			e.Message = util.PrettyPrintErrorMessage(e.Message)
 		}
 		pass.Report(e)

nilaway_test.go

@@ -19,6 +19,7 @@ import (
 	"os"
 	"testing"
 
+	"github.com/stretchr/testify/require"
 	"go.uber.org/nilaway/config"
 	"golang.org/x/tools/go/analysis/analysistest"
 )
@@ -216,9 +217,25 @@ func TestGenerics(t *testing.T) {
 	analysistest.Run(t, testdata, Analyzer, "go.uber.org/generics")
 }
 
+func TestPrettyPrint(t *testing.T) { //nolint:paralleltest
+	// We specifically do not set this test to be parallel such that this test is run separately
+	// from the parallel tests. This makes it possible to set the pretty-print flag to true for
+	// testing and false for the other tests.
+	err := config.Analyzer.Flags.Set(config.PrettyPrintFlag, "true")
+	require.NoError(t, err)
+	defer func() {
+		err := config.Analyzer.Flags.Set(config.PrettyPrintFlag, "false")
+		require.NoError(t, err)
+	}()
+
+	testdata := analysistest.TestData()
+	analysistest.Run(t, testdata, Analyzer, "prettyprint")
+}
+
 func TestMain(m *testing.M) {
-	config.IsTestEnvironment = true
 	flags := map[string]string{
+		// Pretty print should be turned off for easier error message matching in test files.
+		config.PrettyPrintFlag:           "false",
 		config.ExcludeFileDocStringsFlag: "@generated,Code generated by",
 		config.ExcludePkgsFlag:           "ignoredpkg1,ignoredpkg2",
 	}

testdata/src/prettyprint/main.go

@@ -0,0 +1,9 @@
+// Package prettyprint is meant to check if our pretty-print flag has effect.
+package prettyprint
+
+func main() {
+	var a *int
+	// Ensure that the ASCII escape code is in the want strings (such that the errors are pretty
+	// printed).
+	print(*a) //want "\u001B"
+}