File: Re-add support to skip CR (`\r`) in `File::get_as_text`

This was removed in #63481, and we confirmed that it's better like this,
but we add back the possibility to strip CR as an option, to optionally
restore the previous behavior.

For performance this is done directly in `String::parse_utf8`.

Also fixes Android `FileAccess::get_line()` as this one _should_ strip CR.

Supersedes #63717.

15 files changed, 74 insertions, 13 deletions

diff --git a/.gitattributes b/.gitattributes
index 45ea6c25e8..8d2fb108ba 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -7,6 +7,8 @@ thirdparty/* linguist-vendored
 * text=auto eol=lf
 # Except for bat files, which are Windows only files
 *.bat eol=crlf
+# And some test files where the EOL matters
+*.test.txt -text
 
 # The above only works properly for Git 2.10+, so for older versions
 # we need to manually list the binary files we don't want modified.
diff --git a/core/core_bind.cpp b/core/core_bind.cpp
index 3f94ff8329..9382e174f1 100644
--- a/core/core_bind.cpp
+++ b/core/core_bind.cpp
@@ -1227,13 +1227,13 @@ Vector<uint8_t> File::get_buffer(int64_t p_length) const {
 	return data;
 }
 
-String File::get_as_text() const {
+String File::get_as_text(bool p_skip_cr) const {
 	ERR_FAIL_COND_V_MSG(f.is_null(), String(), "File must be opened before use, or is lacking read-write permission.");
 
 	uint64_t original_pos = f->get_position();
 	const_cast<FileAccess *>(*f)->seek(0);
 
-	String text = f->get_as_utf8_string();
+	String text = f->get_as_utf8_string(p_skip_cr);
 
 	const_cast<FileAccess *>(*f)->seek(original_pos);
 
@@ -1430,7 +1430,7 @@ void File::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_buffer", "length"), &File::get_buffer);
 	ClassDB::bind_method(D_METHOD("get_line"), &File::get_line);
 	ClassDB::bind_method(D_METHOD("get_csv_line", "delim"), &File::get_csv_line, DEFVAL(","));
-	ClassDB::bind_method(D_METHOD("get_as_text"), &File::get_as_text);
+	ClassDB::bind_method(D_METHOD("get_as_text", "skip_cr"), &File::get_as_text, DEFVAL(false));
 	ClassDB::bind_method(D_METHOD("get_md5", "path"), &File::get_md5);
 	ClassDB::bind_method(D_METHOD("get_sha256", "path"), &File::get_sha256);
 	ClassDB::bind_method(D_METHOD("is_big_endian"), &File::is_big_endian);
diff --git a/core/core_bind.h b/core/core_bind.h
index 3a4faa3422..7564bdc7e3 100644
--- a/core/core_bind.h
+++ b/core/core_bind.h
@@ -411,7 +411,7 @@ public:
 	Vector<uint8_t> get_buffer(int64_t p_length) const; // Get an array of bytes.
 	String get_line() const;
 	Vector<String> get_csv_line(const String &p_delim = ",") const;
-	String get_as_text() const;
+	String get_as_text(bool p_skip_cr = false) const;
 	String get_md5(const String &p_path) const;
 	String get_sha256(const String &p_path) const;
 
diff --git a/core/io/file_access.cpp b/core/io/file_access.cpp
index da25f23917..8ed3d40c22 100644
--- a/core/io/file_access.cpp
+++ b/core/io/file_access.cpp
@@ -377,7 +377,7 @@ uint64_t FileAccess::get_buffer(uint8_t *p_dst, uint64_t p_length) const {
 	return i;
 }
 
-String FileAccess::get_as_utf8_string() const {
+String FileAccess::get_as_utf8_string(bool p_skip_cr) const {
 	Vector<uint8_t> sourcef;
 	uint64_t len = get_length();
 	sourcef.resize(len + 1);
@@ -388,7 +388,7 @@ String FileAccess::get_as_utf8_string() const {
 	w[len] = 0;
 
 	String s;
-	s.parse_utf8((const char *)w);
+	s.parse_utf8((const char *)w, -1, p_skip_cr);
 	return s;
 }
 
diff --git a/core/io/file_access.h b/core/io/file_access.h
index e2c11142d7..3386800686 100644
--- a/core/io/file_access.h
+++ b/core/io/file_access.h
@@ -113,7 +113,7 @@ public:
 	virtual String get_line() const;
 	virtual String get_token() const;
 	virtual Vector<String> get_csv_line(const String &p_delim = ",") const;
-	virtual String get_as_utf8_string() const;
+	virtual String get_as_utf8_string(bool p_skip_cr = false) const;
 
 	/**
 	 * Use this for files WRITTEN in _big_ endian machines (ie, amiga/mac)
diff --git a/core/string/ustring.cpp b/core/string/ustring.cpp
index beefe54faf..e93375bff7 100644
--- a/core/string/ustring.cpp
+++ b/core/string/ustring.cpp
@@ -1656,7 +1656,7 @@ String String::utf8(const char *p_utf8, int p_len) {
 	return ret;
 }
 
-Error String::parse_utf8(const char *p_utf8, int p_len) {
+Error String::parse_utf8(const char *p_utf8, int p_len, bool p_skip_cr) {
 	if (!p_utf8) {
 		return ERR_INVALID_DATA;
 	}
@@ -1689,6 +1689,10 @@ Error String::parse_utf8(const char *p_utf8, int p_len) {
 			uint8_t c = *ptrtmp >= 0 ? *ptrtmp : uint8_t(256 + *ptrtmp);
 
 			if (skip == 0) {
+				if (p_skip_cr && c == '\r') {
+					ptrtmp++;
+					continue;
+				}
 				/* Determine the number of characters in sequence */
 				if ((c & 0x80) == 0) {
 					skip = 0;
@@ -1753,6 +1757,10 @@ Error String::parse_utf8(const char *p_utf8, int p_len) {
 		uint8_t c = *p_utf8 >= 0 ? *p_utf8 : uint8_t(256 + *p_utf8);
 
 		if (skip == 0) {
+			if (p_skip_cr && c == '\r') {
+				p_utf8++;
+				continue;
+			}
 			/* Determine the number of characters in sequence */
 			if ((c & 0x80) == 0) {
 				*(dst++) = c;
diff --git a/core/string/ustring.h b/core/string/ustring.h
index 7672663964..6c3169f136 100644
--- a/core/string/ustring.h
+++ b/core/string/ustring.h
@@ -377,7 +377,7 @@ public:
 
 	CharString ascii(bool p_allow_extended = false) const;
 	CharString utf8() const;
-	Error parse_utf8(const char *p_utf8, int p_len = -1);
+	Error parse_utf8(const char *p_utf8, int p_len = -1, bool p_skip_cr = false);
 	static String utf8(const char *p_utf8, int p_len = -1);
 
 	Char16String utf16() const;
diff --git a/doc/classes/File.xml b/doc/classes/File.xml
index 0b4a8fa46e..3a2776ff21 100644
--- a/doc/classes/File.xml
+++ b/doc/classes/File.xml
@@ -115,9 +115,10 @@
 		</method>
 		<method name="get_as_text" qualifiers="const">
 			<return type="String" />
+			<argument index="0" name="skip_cr" type="bool" default="false" />
 			<description>
-				Returns the whole file as a [String].
-				Text is interpreted as being UTF-8 encoded.
+				Returns the whole file as a [String]. Text is interpreted as being UTF-8 encoded.
+				If [code]skip_cr[/code] is [code]true[/code], carriage return characters ([code]\r[/code], CR) will be ignored when parsing the UTF-8, so that only line feed characters ([code]\n[/code], LF) represent a new line (Unix convention).
 			</description>
 		</method>
 		<method name="get_buffer" qualifiers="const">
diff --git a/misc/scripts/file_format.sh b/misc/scripts/file_format.sh
index c767d3f8a0..731b3ee005 100755
--- a/misc/scripts/file_format.sh
+++ b/misc/scripts/file_format.sh
@@ -37,6 +37,8 @@ while IFS= read -rd '' f; do
         continue
     elif [[ "$f" == *"-so_wrap."* ]]; then
         continue
+    elif [[ "$f" == *".test.txt" ]]; then
+        continue
     fi
     # Ensure that files are UTF-8 formatted.
     recode UTF-8 "$f" 2> /dev/null
diff --git a/platform/android/file_access_filesystem_jandroid.cpp b/platform/android/file_access_filesystem_jandroid.cpp
index 733d92f741..6b21c18d59 100644
--- a/platform/android/file_access_filesystem_jandroid.cpp
+++ b/platform/android/file_access_filesystem_jandroid.cpp
@@ -29,9 +29,11 @@
 /*************************************************************************/
 
 #include "file_access_filesystem_jandroid.h"
+
 #include "core/os/os.h"
 #include "core/templates/local_vector.h"
 #include "thread_jandroid.h"
+
 #include <unistd.h>
 
 jobject FileAccessFilesystemJAndroid::file_access_handler = nullptr;
@@ -198,7 +200,7 @@ String FileAccessFilesystemJAndroid::get_line() const {
 			if (elem == '\n' || elem == '\0') {
 				// Found the end of the line
 				const_cast<FileAccessFilesystemJAndroid *>(this)->seek(start_position + line_buffer_position + 1);
-				if (result.parse_utf8((const char *)line_buffer.ptr(), line_buffer_position)) {
+				if (result.parse_utf8((const char *)line_buffer.ptr(), line_buffer_position, true)) {
 					return String();
 				}
 				return result;
@@ -206,7 +208,7 @@ String FileAccessFilesystemJAndroid::get_line() const {
 		}
 	}
 
-	if (result.parse_utf8((const char *)line_buffer.ptr(), line_buffer_position)) {
+	if (result.parse_utf8((const char *)line_buffer.ptr(), line_buffer_position, true)) {
 		return String();
 	}
 	return result;
diff --git a/tests/core/io/test_file_access.h b/tests/core/io/test_file_access.h
index f0e1cceacf..aab62955cb 100644
--- a/tests/core/io/test_file_access.h
+++ b/tests/core/io/test_file_access.h
@@ -78,6 +78,29 @@ TEST_CASE("[FileAccess] CSV read") {
 	CHECK(row5[1] == "tab separated");
 	CHECK(row5[2] == "lines, good?");
 }
+
+TEST_CASE("[FileAccess] Get as UTF-8 String") {
+	Ref<FileAccess> f_lf = FileAccess::open(TestUtils::get_data_path("line_endings_lf.test.txt"), FileAccess::READ);
+	String s_lf = f_lf->get_as_utf8_string();
+	f_lf->seek(0);
+	String s_lf_nocr = f_lf->get_as_utf8_string(true);
+	CHECK(s_lf == "Hello darkness\nMy old friend\nI've come to talk\nWith you again\n");
+	CHECK(s_lf_nocr == "Hello darkness\nMy old friend\nI've come to talk\nWith you again\n");
+
+	Ref<FileAccess> f_crlf = FileAccess::open(TestUtils::get_data_path("line_endings_crlf.test.txt"), FileAccess::READ);
+	String s_crlf = f_crlf->get_as_utf8_string();
+	f_crlf->seek(0);
+	String s_crlf_nocr = f_crlf->get_as_utf8_string(true);
+	CHECK(s_crlf == "Hello darkness\r\nMy old friend\r\nI've come to talk\r\nWith you again\r\n");
+	CHECK(s_crlf_nocr == "Hello darkness\nMy old friend\nI've come to talk\nWith you again\n");
+
+	Ref<FileAccess> f_cr = FileAccess::open(TestUtils::get_data_path("line_endings_cr.test.txt"), FileAccess::READ);
+	String s_cr = f_cr->get_as_utf8_string();
+	f_cr->seek(0);
+	String s_cr_nocr = f_cr->get_as_utf8_string(true);
+	CHECK(s_cr == "Hello darkness\rMy old friend\rI've come to talk\rWith you again\r");
+	CHECK(s_cr_nocr == "Hello darknessMy old friendI've come to talkWith you again");
+}
 } // namespace TestFileAccess
 
 #endif // TEST_FILE_ACCESS_H
diff --git a/tests/core/string/test_string.h b/tests/core/string/test_string.h
index 0c5704d6c9..b8b766023a 100644
--- a/tests/core/string/test_string.h
+++ b/tests/core/string/test_string.h
@@ -152,6 +152,20 @@ TEST_CASE("[String] UTF16 with BOM") {
 	CHECK(String::utf16(cs) == s);
 }
 
+TEST_CASE("[String] UTF8 with CR") {
+	const String base = U"Hello darkness\r\nMy old friend\nI've come to talk\rWith you again";
+
+	String keep_cr;
+	Error err = keep_cr.parse_utf8(base.utf8().get_data());
+	CHECK(err == OK);
+	CHECK(keep_cr == base);
+
+	String no_cr;
+	err = no_cr.parse_utf8(base.utf8().get_data(), -1, true); // Skip CR.
+	CHECK(err == OK);
+	CHECK(no_cr == base.replace("\r", ""));
+}
+
 TEST_CASE("[String] Invalid UTF8 (non-standard)") {
 	ERR_PRINT_OFF
 	static const uint8_t u8str[] = { 0x45, 0xE3, 0x81, 0x8A, 0xE3, 0x82, 0x88, 0xE3, 0x81, 0x86, 0xF0, 0x9F, 0x8E, 0xA4, 0xF0, 0x82, 0x82, 0xAC, 0xED, 0xA0, 0x81, 0 };
diff --git a/tests/data/line_endings_cr.test.txt b/tests/data/line_endings_cr.test.txt
new file mode 100644
index 0000000000..556154bb25
--- /dev/null
+++ b/tests/data/line_endings_cr.test.txt
@@ -0,0 +1 @@
+Hello darkness
My old friend
I've come to talk
With you again
\ No newline at end of file
diff --git a/tests/data/line_endings_crlf.test.txt b/tests/data/line_endings_crlf.test.txt
new file mode 100644
index 0000000000..a3cbe55b7f
--- /dev/null
+++ b/tests/data/line_endings_crlf.test.txt
@@ -0,0 +1,4 @@
+Hello darkness

+My old friend

+I've come to talk

+With you again

diff --git a/tests/data/line_endings_lf.test.txt b/tests/data/line_endings_lf.test.txt
new file mode 100644
index 0000000000..0aabcd911e
--- /dev/null
+++ b/tests/data/line_endings_lf.test.txt
@@ -0,0 +1,4 @@
+Hello darkness
+My old friend
+I've come to talk
+With you again