FIXUP: Switch from bufio.Scanner to strings.Lines

Author: cbandy

internal/testing/cmp/cmp.go

@@ -5,7 +5,6 @@
 package cmp
 
 import (
-	"bufio"
 	"regexp"
 	"strings"
 
@@ -98,11 +97,14 @@ var leadingTabs = regexp.MustCompile(`^\t+`)
 // dedentLines finds the shortest leading whitespace of every line in data and then removes it from every line.
 // When tabWidth is positive, leading tabs are converted to spaces first.
 func dedentLines(data string, tabWidth int) string {
+	if len(data) < 1 {
+		return ""
+	}
+
 	var lines = make([]string, 0, 20)
 	var lowest, highest string
 
-	for s := bufio.NewScanner(strings.NewReader(data)); s.Scan(); {
-		line := s.Text()
+	for line := range strings.Lines(data) {
 		tabs := leadingTabs.FindString(line)
 
 		// Replace any leading tabs with spaces when tabWidth is positive.
@@ -137,14 +139,10 @@ func dedentLines(data string, tabWidth int) string {
 			if len(lines[i]) > width {
 				lines[i] = lines[i][width:]
 			} else {
-				lines[i] = ""
+				lines[i] = "\n"
 			}
 		}
 	}
 
-	result := strings.Join(lines, "\n")
-	if len(lines) > 0 {
-		result += "\n"
-	}
-	return result
+	return strings.TrimSuffix(strings.Join(lines, ""), "\n") + "\n"
 }

internal/testing/cmp/cmp_test.go

@@ -55,6 +55,9 @@ func TestDedentLines(t *testing.T) {
 		{input: "  ", expected: "\n"},
 		{input: "\t", expected: "\n"},
 		{input: "\t\t", expected: "\n"},
+
+		// blank lines preserved
+		{input: " ~\n\n ~\n", expected: "~\n\n~\n"},
 	} {
 		t.Run(fmt.Sprintf("%v:%#v", tc.width, tc.input), func(t *testing.T) {
 			assert.DeepEqual(t, dedentLines(tc.input, tc.width), tc.expected)

pkg/apis/postgres-operator.crunchydata.com/v1beta1/cmp_test.go

@@ -5,7 +5,6 @@
 package v1beta1_test
 
 import (
-	"bufio"
 	"fmt"
 	"regexp"
 	"strings"
@@ -32,11 +31,14 @@ var leadingTabs = regexp.MustCompile(`^\t+`)
 // dedentLines finds the shortest leading whitespace of every line in data and then removes it from every line.
 // When tabWidth is positive, leading tabs are converted to spaces first.
 func dedentLines(data string, tabWidth int) string {
+	if len(data) < 1 {
+		return ""
+	}
+
 	var lines = make([]string, 0, 20)
 	var lowest, highest string
 
-	for s := bufio.NewScanner(strings.NewReader(data)); s.Scan(); {
-		line := s.Text()
+	for line := range strings.Lines(data) {
 		tabs := leadingTabs.FindString(line)
 
 		// Replace any leading tabs with spaces when tabWidth is positive.
@@ -71,16 +73,12 @@ func dedentLines(data string, tabWidth int) string {
 			if len(lines[i]) > width {
 				lines[i] = lines[i][width:]
 			} else {
-				lines[i] = ""
+				lines[i] = "\n"
 			}
 		}
 	}
 
-	result := strings.Join(lines, "\n")
-	if len(lines) > 0 {
-		result += "\n"
-	}
-	return result
+	return strings.TrimSuffix(strings.Join(lines, ""), "\n") + "\n"
 }
 
 func TestDedentLines(t *testing.T) {
@@ -127,6 +125,9 @@ func TestDedentLines(t *testing.T) {
 		{input: "  ", expected: "\n"},
 		{input: "\t", expected: "\n"},
 		{input: "\t\t", expected: "\n"},
+
+		// blank lines preserved
+		{input: " ~\n\n ~\n", expected: "~\n\n~\n"},
 	} {
 		t.Run(fmt.Sprintf("%v:%#v", tc.width, tc.input), func(t *testing.T) {
 			assert.DeepEqual(t, dedentLines(tc.input, tc.width), tc.expected)