Switch to bufio.Reader.Readline (#234)

Co-authored-by: Szabolcs Toth <szabolcs.toth@bitrise.io>

Author: godrei

xcodebuild/show_build_settings.go

@@ -2,7 +2,9 @@ package xcodebuild
 
 import (
 	"bufio"
+	"bytes"
 	"fmt"
+	"io"
 	"path/filepath"
 	"strings"
 
@@ -97,21 +99,35 @@ func (c ShowBuildSettingsCommandModel) PrintableCmd() string {
 func parseBuildSettings(out string) (serialized.Object, error) {
 	settings := serialized.Object{}
 
-	scanner := bufio.NewScanner(strings.NewReader(out))
-	for scanner.Scan() {
-		line := strings.TrimSpace(scanner.Text())
+	reader := bufio.NewReader(strings.NewReader(out))
+	var buffer bytes.Buffer
 
-		if split := strings.Split(line, "="); len(split) > 1 {
-			key := strings.TrimSpace(split[0])
-			value := strings.TrimSpace(strings.Join(split[1:], "="))
-			value = strings.Trim(value, `"`)
+	for {
+		b, isPrefix, err := reader.ReadLine()
+		if err == io.EOF {
+			break
+		} else if err != nil {
+			return nil, err
+		}
+
+		lineFragment := string(b)
+		buffer.WriteString(lineFragment)
+
+		// isPrefix is set to false once a full line has been read
+		if isPrefix == false {
+			line := strings.TrimSpace(buffer.String())
 
-			settings[key] = value
+			if split := strings.Split(line, "="); len(split) > 1 {
+				key := strings.TrimSpace(split[0])
+				value := strings.TrimSpace(strings.Join(split[1:], "="))
+				value = strings.Trim(value, `"`)
+
+				settings[key] = value
+			}
+
+			buffer.Reset()
 		}
 	}
-	if err := scanner.Err(); err != nil {
-		return nil, err
-	}
 
 	return settings, nil
 }

xcodebuild/show_build_settings_test.go

@@ -1,6 +1,7 @@
 package xcodebuild
 
 import (
+	"os"
 	"testing"
 
 	"github.com/bitrise-io/go-xcode/xcodeproject/serialized"
@@ -74,6 +75,28 @@ func Test_parseShowBuildSettingsOutput(t *testing.T) {
 	}
 }
 
+func TestReadLongBuildSettingsLine(t *testing.T) {
+	// The default line limit for a bufio.Scanner is 65000 characters, and this fie contains a line longer than that
+	buildSettingsWithLongLine, err := os.ReadFile("./testdata/buildSettingsWithLongLine.txt")
+	require.NoError(t, err)
+
+	got, err := parseBuildSettings(string(buildSettingsWithLongLine))
+	require.NoError(t, err)
+
+	// Reading the same single long line value from a file, so it does not hurt test readability
+	expectedSingleLongLine, err := os.ReadFile("./testdata/expectedSingleLongLine.txt")
+	require.NoError(t, err)
+
+	want := serialized.Object{
+		"ACTION":                      "build",
+		"AD_HOC_CODE_SIGNING_ALLOWED": "NO",
+		"REALLY_LONG_LINE":            string(expectedSingleLongLine),
+		"ALTERNATE_GROUP":             "staff",
+		"BUILD_STYLE":                 "fast",
+	}
+	require.Equal(t, want, got)
+}
+
 const testBuildSettingsOut = `Build settings for action build and target sample-apps-osx-10-12:
     VERSION_INFO_STRING = "@(#)PROGRAM:sample-apps-osx-10-12  PROJECT:sample-apps-osx-10-12-"
     AVAILABLE_PLATFORMS = appletvos appletvsimulator iphoneos iphonesimulator macosx watchos watchsimulator