1 files changed, 155 insertions, 0 deletions
diff --git a/integrationtests/dgrep_line_endings_test.go b/integrationtests/dgrep_line_endings_test.go
new file mode 100644
index 0000000..3d28e5c
--- /dev/null
+++ b/integrationtests/dgrep_line_endings_test.go
@@ -0,0 +1,155 @@
+package integrationtests
+
+import (
+	"os"
+	"os/exec"
+	"strings"
+	"testing"
+
+	"github.com/mimecast/dtail/internal/config"
+)
+
+// TestDGrepLineEndings verifies that dgrep preserves line endings correctly
+func TestDGrepLineEndings(t *testing.T) {
+	if !config.Env("DTAIL_INTEGRATION_TEST_RUN_MODE") {
+		t.Log("Skipping")
+		return
+	}
+
+	// Create a test file with various content
+	testContent := `Line 1 with pattern
+Line 2 no test
+Line 3 with pattern again
+Line 4 no test
+Line 5 final pattern`
+	
+	testFile := "test_grep_line_endings.txt"
+	if err := os.WriteFile(testFile, []byte(testContent), 0644); err != nil {
+		t.Fatalf("Failed to create test file: %v", err)
+	}
+	defer os.Remove(testFile)
+
+	t.Run("BasicGrep", func(t *testing.T) {
+		// Run dgrep searching for "pattern"
+		cmd := exec.Command("../dgrep", "--cfg", "none", "--grep", "pattern", testFile)
+		output, err := cmd.Output()
+		if err != nil {
+			t.Fatalf("dgrep command failed: %v", err)
+		}
+
+		// Should get 3 matching lines, each with proper line ending
+		outputStr := string(output)
+		lines := strings.Split(strings.TrimRight(outputStr, "\n"), "\n")
+		if len(lines) != 3 {
+			t.Errorf("Expected 3 matching lines, got %d lines. Output:\n%s", 
+				len(lines), outputStr)
+		}
+
+		// Verify each line contains "pattern"
+		for i, line := range lines {
+			if !strings.Contains(line, "pattern") {
+				t.Errorf("Line %d should contain 'pattern': %s", i, line)
+			}
+		}
+	})
+
+	t.Run("WithContext", func(t *testing.T) {
+		// Test with before and after context
+		cmd := exec.Command("../dgrep", "--cfg", "none", 
+			"--before", "1", "--after", "1", "--grep", "Line 3", testFile)
+		output, err := cmd.Output()
+		if err != nil {
+			t.Fatalf("dgrep command failed: %v", err)
+		}
+
+		// Should get Line 2 (before), Line 3 (match), Line 4 (after)
+		lines := strings.Split(strings.TrimRight(string(output), "\n"), "\n")
+		if len(lines) != 3 {
+			t.Errorf("Expected 3 lines with context, got %d. Output:\n%s", 
+				len(lines), string(output))
+		}
+
+		// Verify the lines
+		if !strings.Contains(lines[0], "Line 2") {
+			t.Errorf("First line should be before context (Line 2): %s", lines[0])
+		}
+		if !strings.Contains(lines[1], "Line 3") {
+			t.Errorf("Second line should be the match (Line 3): %s", lines[1])
+		}
+		if !strings.Contains(lines[2], "Line 4") {
+			t.Errorf("Third line should be after context (Line 4): %s", lines[2])
+		}
+	})
+
+	t.Run("NoMatches", func(t *testing.T) {
+		// Test with pattern that doesn't match
+		cmd := exec.Command("../dgrep", "--cfg", "none", "--grep", "nonexistent", testFile)
+		output, err := cmd.Output()
+		if err != nil {
+			t.Fatalf("dgrep command failed: %v", err)
+		}
+
+		// Should get empty output
+		if len(output) != 0 {
+			t.Errorf("Expected empty output for no matches, got: %q", string(output))
+		}
+	})
+
+	t.Run("PlainMode", func(t *testing.T) {
+		// Test with --plain flag
+		cmd := exec.Command("../dgrep", "--plain", "--cfg", "none", "--grep", "pattern", testFile)
+		output, err := cmd.Output()
+		if err != nil {
+			t.Fatalf("dgrep command failed: %v", err)
+		}
+
+		// In plain mode, should still have proper line endings
+		outputStr := string(output)
+		lines := strings.Split(strings.TrimRight(outputStr, "\n"), "\n")
+		if len(lines) != 3 {
+			t.Errorf("Plain mode: Expected 3 matching lines, got %d lines", 
+				len(lines))
+		}
+	})
+
+	t.Run("MultipleFiles", func(t *testing.T) {
+		// Create additional test files
+		testFile2 := "test_grep_line_endings2.txt"
+		testFile3 := "test_grep_line_endings3.txt"
+		
+		content2 := "File 2 with pattern\nFile 2 no test\n"
+		content3 := "File 3 no test\nFile 3 with pattern\n"
+		
+		if err := os.WriteFile(testFile2, []byte(content2), 0644); err != nil {
+			t.Fatalf("Failed to create test file 2: %v", err)
+		}
+		defer os.Remove(testFile2)
+		
+		if err := os.WriteFile(testFile3, []byte(content3), 0644); err != nil {
+			t.Fatalf("Failed to create test file 3: %v", err)
+		}
+		defer os.Remove(testFile3)
+
+		// Run dgrep with multiple files
+		cmd := exec.Command("../dgrep", "--cfg", "none", "--grep", "pattern",
+			testFile, testFile2, testFile3)
+		output, err := cmd.Output()
+		if err != nil {
+			t.Fatalf("dgrep command failed: %v", err)
+		}
+
+		// Should get 5 matching lines total (3 + 1 + 1)
+		lines := strings.Split(strings.TrimRight(string(output), "\n"), "\n")
+		if len(lines) != 5 {
+			t.Errorf("Expected 5 matching lines from multiple files, got %d. Output:\n%s", 
+				len(lines), string(output))
+		}
+
+		// Verify all lines contain "pattern"
+		for i, line := range lines {
+			if !strings.Contains(line, "pattern") {
+				t.Errorf("Line %d should contain 'pattern': %s", i, line)
+			}
+		}
+	})
+}
+\ No newline at end of file