apply: add unit tests for parse_range and rename parse_range to parse…

…_fragment_range

This patchset makes the parse_range function in apply be non-internal linkage
in order to expose to the unit testing framework. In so doing, because there is
another function called parse_range, I gave this one a more specific name,
parse_fragment_range. Other than that, this commit adds several test cases
(positive and negative) for the function.

Signed-off-by: Philip Peterson <philip.c.peterson@gmail.com>

Makefile

@@ -1339,6 +1339,7 @@ THIRD_PARTY_SOURCES += compat/regex/%
 THIRD_PARTY_SOURCES += sha1collisiondetection/%
 THIRD_PARTY_SOURCES += sha1dc/%
 
+UNIT_TEST_PROGRAMS += t-apply
 UNIT_TEST_PROGRAMS += t-basic
 UNIT_TEST_PROGRAMS += t-mem-pool
 UNIT_TEST_PROGRAMS += t-strbuf

apply.c

@@ -1430,8 +1430,8 @@ static int parse_num(const char *line, unsigned long *p)
 	return ptr - line;
 }
 
-static int parse_range(const char *line, int len, int offset, const char *expect,
-		       unsigned long *p1, unsigned long *p2)
+int parse_fragment_range(const char *line, int len, int offset, const char *expect,
+			 unsigned long *p1, unsigned long *p2)
 {
 	int digits, ex;
 
@@ -1530,8 +1530,8 @@ static int parse_fragment_header(const char *line, int len, struct fragment *fra
 		return -1;
 
 	/* Figure out the number of lines in a fragment */
-	offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
-	offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
+	offset = parse_fragment_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
+	offset = parse_fragment_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
 
 	return offset;
 }

apply.h

@@ -187,3 +187,7 @@ int apply_all_patches(struct apply_state *state,
 		      int options);
 
 #endif
+
+
+int parse_fragment_range(const char *line, int len, int offset, const char *expect,
+		       unsigned long *p1, unsigned long *p2);

t/unit-tests/t-apply.c

@@ -0,0 +1,67 @@
+#include "test-lib.h"
+#include "apply.h"
+
+#define FAILURE -1
+
+static void setup_static(const char *line, int len, int offset,
+						 const char *expect, int assert_result,
+						 unsigned long assert_p1,
+						 unsigned long assert_p2)
+{
+	unsigned long p1 = 9999;
+	unsigned long p2 = 9999;
+	int result = parse_fragment_range(line, len, offset, expect, &p1, &p2);
+	check_int(result, ==, assert_result);
+	check_int(p1, ==, assert_p1);
+	check_int(p2, ==, assert_p2);
+}
+
+int cmd_main(int argc, const char **argv)
+{
+	char* text;
+	int expected_result;
+
+	/* Success */
+	text = "@@ -4,4 +";
+	expected_result = 9;
+	TEST(setup_static(text, strlen(text), 4, " +", expected_result, 4, 4),
+		 "well-formed range");
+
+	text = "@@ -4 +8 @@";
+	expected_result = 7;
+	TEST(setup_static(text, strlen(text), 4, " +", expected_result, 4, 1),
+		 "non-comma range");
+
+	/* Failure */
+	text = "@@ -X,4 +";
+	expected_result = FAILURE;
+	TEST(setup_static(text, strlen(text), 4, " +", expected_result, 9999, 9999),
+		 "non-digit range (first coordinate)");
+
+	text = "@@ -4,X +";
+	expected_result = FAILURE;
+	TEST(setup_static(text, strlen(text), 4, " +", expected_result, 4, 1), // p2 is 1, a little strange but not catastrophic
+		 "non-digit range (second coordinate)");
+
+	text = "@@ -4,4 -";
+	expected_result = FAILURE;
+	TEST(setup_static(text, strlen(text), 4, " +", expected_result, 4, 4),
+		 "non-expected trailing text");
+
+	text = "@@ -4,4";
+	expected_result = FAILURE;
+	TEST(setup_static(text, strlen(text), 4, " +", expected_result, 4, 4),
+		 "not long enough for expected trailing text");
+
+	text = "@@ -4,4";
+	expected_result = FAILURE;
+	TEST(setup_static(text, strlen(text), 7, " +", expected_result, 9999, 9999),
+		 "not long enough for offset");
+
+	text = "@@ -4,4";
+	expected_result = FAILURE;
+	TEST(setup_static(text, strlen(text), -1, " +", expected_result, 9999, 9999),
+		 "negative offset");
+
+	return test_done();
+}