Fix scanning for the best intended match

filecheck/FileCheck.py

@@ -28,6 +28,11 @@ class CheckType(Enum):
 Check = namedtuple("Check", "check_type match_type expression source_line check_line_idx start_index")
 
 
+def debug_print(string):
+    # print(string)
+    pass
+
+
 def similar(a, b):
     return SequenceMatcher(None, a, b).ratio()
 
@@ -81,13 +86,13 @@ def canonicalize_whitespace(input):
 
 
 def dump_check(check):
-    print("check dump")
-    print("\tcheck_type: {}".format(check.check_type))
-    print("\tmatch_type: {}".format(check.match_type))
-    print("\texpression: {}".format(check.expression))
-    print("\tsource_line: {}".format(check.source_line))
-    print("\tcheck_line_idx: {}".format(check.check_line_idx))
-    print("\tstart_index: {}".format(check.start_index))
+    debug_print("check dump")
+    debug_print("\tcheck_type: {}".format(check.check_type))
+    debug_print("\tmatch_type: {}".format(check.match_type))
+    debug_print("\texpression: {}".format(check.expression))
+    debug_print("\tsource_line: {}".format(check.source_line))
+    debug_print("\tcheck_line_idx: {}".format(check.check_line_idx))
+    debug_print("\tstart_index: {}".format(check.start_index))
 
 
 def main():
@@ -313,15 +318,6 @@ def main():
         if current_check.match_type == MatchType.SUBSTRING:
             last_read_line = input_lines[current_scan_base]
 
-            candidate_line = None
-            current_best_ratio = 0
-            for read_line in input_lines[current_scan_base:]:
-                similar_ratio = similar(last_read_line, current_check.expression)
-                if current_best_ratio < similar_ratio:
-                    candidate_line = read_line
-                    current_best_ratio = similar_ratio
-            assert candidate_line
-
             print("{}:{}:{}: error: CHECK: expected string not found in input"
                   .format(check_file,
                           current_check.check_line_idx + 1,
@@ -333,10 +329,19 @@ def main():
             print(last_read_line)
             print("^")
 
-            caret_pos = len(candidate_line) // 2 + 1
-            print("<stdin>:{}:{}: note: possible intended match here".format(current_scan_base + 1, caret_pos))
-            print(candidate_line)
-            print("^".rjust(caret_pos, ' '))
+            candidate_line = None
+            current_best_ratio = 0
+            for read_line in input_lines[current_scan_base:]:
+                similar_ratio = similar(read_line, current_check.expression)
+                if current_best_ratio < similar_ratio:
+                    candidate_line = read_line
+                    current_best_ratio = similar_ratio
+            if candidate_line:
+                caret_pos = len(candidate_line) // 2 + 1
+                print("<stdin>:{}:{}: note: possible intended match here".format(current_scan_base + 1, caret_pos))
+                print(candidate_line)
+                print("^".rjust(caret_pos, ' '))
+
             exit(1)
 
         if current_check.match_type == MatchType.REGEX:

tests/integration/tests/check_commands/CHECK/three_strings/04-negative_match_first_string_scanning_for_the_best_match/filecheck.check

@@ -0,0 +1,3 @@
+; CHECK: foo
+; CHECK: hello2
+; CHECK: hello3

tests/integration/tests/check_commands/CHECK/three_strings/04-negative_match_first_string_scanning_for_the_best_match/filecheck.input

@@ -0,0 +1,3 @@
+hello1
+hello2
+fo

tests/integration/tests/check_commands/CHECK/three_strings/04-negative_match_first_string_scanning_for_the_best_match/sample.itest

@@ -0,0 +1,14 @@
+; RUN: cat %S/filecheck.input | (%FILECHECK_EXEC %S/filecheck.check 2>&1; test $? = 1) | %FILECHECK_TESTER_EXEC %s --match-full-lines
+; CHECK: {{^.*}}FileCheck{{(\.py)?$}}
+; CHECK-NEXT: {{.*filecheck.check:1:.*: error: CHECK: expected string not found in input$}}
+; CHECK-NEXT: {{^}}; CHECK: foo{{$}}
+; CHECK-NEXT: {{^}}         ^{{$}}
+; CHECK-NEXT: {{^<stdin>:.*:.*: note: scanning from here$}}
+; CHECK-NEXT: hello1
+; CHECK-NEXT: {{^\^$}}
+; CHECK-NEXT: {{^<stdin>:.*:.*: note: possible intended match here$}}
+; CHECK-NEXT: {{^fo$}}
+
+; TODO: https://github.com/stanislaw/FileCheck.py/issues/38
+; CHECK-NEXT: {{^ ?\^$}}
+; CHECK-EMPTY:

tests/integration/tests/check_commands/CHECK/three_strings/05-negative_match_first_string_no_best_match/filecheck.check

@@ -0,0 +1,3 @@
+; CHECK: foo
+; CHECK: hello2
+; CHECK: hello3

tests/integration/tests/check_commands/CHECK/three_strings/05-negative_match_first_string_no_best_match/filecheck.input

@@ -0,0 +1,3 @@
+bar
+bar
+bar

tests/integration/tests/check_commands/CHECK/three_strings/05-negative_match_first_string_no_best_match/sample.itest

@@ -0,0 +1,9 @@
+; RUN: cat %S/filecheck.input | (%FILECHECK_EXEC %S/filecheck.check 2>&1; test $? = 1) | %FILECHECK_TESTER_EXEC %s --match-full-lines
+; CHECK: {{^.*}}FileCheck{{(\.py)?$}}
+; CHECK-NEXT: {{.*filecheck.check:1:.*: error: CHECK: expected string not found in input$}}
+; CHECK-NEXT: {{^}}; CHECK: foo{{$}}
+; CHECK-NEXT: {{^}}         ^{{$}}
+; CHECK-NEXT: {{^<stdin>:.*:.*: note: scanning from here$}}
+; CHECK-NEXT: {{^bar$}}
+; CHECK-NEXT: {{^\^$}}
+; CHECK-EMPTY: