Fix a crash error in debug build.

* Fixed DateRewriter::IsNDigits to exclude negative values.
* #878

#codehealth

PiperOrigin-RevId: 633099245

src/data/test/session/scenario/t13n_negative_number.txt

@@ -0,0 +1,17 @@
+# This file tests ConvertToHalfAscii against a negative number (F10 to -123)
+
+# Enable IME
+SEND_KEY	ON
+RESET_CONTEXT
+SWITCH_INPUT_MODE	HIRAGANA
+
+################################################################################
+# Test for MS-IME keymap
+SET_CONFIG	session_keymap	MSIME
+
+# Verify that input is learned.
+SEND_KEYS	-123
+SEND_KEY	F10
+EXPECT_PREEDIT	-123
+
+RESET_CONTEXT

src/rewriter/BUILD.bazel

@@ -223,6 +223,7 @@ mozc_cc_library(
         "//base:number_util",
         "//base:util",
         "//base:vlog",
+        "//base/strings:unicode",
         "//composer",
         "//converter:converter_interface",
         "//converter:segments",

src/rewriter/date_rewriter.cc

@@ -62,6 +62,7 @@
 #include "base/clock.h"
 #include "base/japanese_util.h"
 #include "base/number_util.h"
+#include "base/strings/unicode.h"
 #include "base/util.h"
 #include "base/vlog.h"
 #include "composer/composer.h"
@@ -1168,8 +1169,15 @@ bool DateRewriter::ResizeSegments(const ConversionRequest &request,
 
 namespace {
 bool IsNDigits(const absl::string_view value, int n) {
-  return Util::CharsLen(value) == n &&
-         Util::GetScriptType(value) == Util::NUMBER;
+  if (Util::CharsLen(value) != n) {
+    return false;
+  }
+  for (absl::string_view c : Utf8AsChars(value)) {
+    if (Util::GetScriptType(c) != Util::NUMBER) {
+      return false;
+    }
+  }
+  return true;
 }
 
 // Gets n digits if possible.

src/rewriter/date_rewriter_test.cc

@@ -1066,6 +1066,31 @@ TEST_F(DateRewriterTest, ConsecutiveDigitsInsertPositionTest) {
   }
 }
 
+TEST_F(DateRewriterTest, ConsecutiveDigitsWithMinusSign) {
+  commands::Request request;
+  const config::Config config;
+  const composer::Composer composer(nullptr, &request, &config);
+  const ConversionRequest conversion_request(&composer, &request, &config);
+
+  // Init an instance of Segments for this test.
+  Segments segments;
+  InitSegment("-123", "−１２３", &segments);
+
+  Segment *segment = segments.mutable_conversion_segment(0);
+  // Hiragana: ー is prolonged sound mark (U+2212)
+  segment->add_meta_candidate()->value = "ー１２３";
+  // Half Ascii: - is hyphen-minus (U+002D)
+  segment->add_meta_candidate()->value = "-123";
+  // Full Ascii: − is minus (U+30FC)
+  segment->add_meta_candidate()->value = "−１２３";
+  // Half Katakana: ｰ is half prolonged sound mark (U+FF70)
+  segment->add_meta_candidate()->value = "ｰ123";
+
+  // No rewrite is expected.
+  DateRewriter rewriter;
+  EXPECT_FALSE(rewriter.Rewrite(conversion_request, &segments));
+}
+
 TEST_F(DateRewriterTest, ConsecutiveDigitsInsertPositionWithHistory) {
   commands::Request request;
   const config::Config config;

src/rewriter/rewriter.gyp

@@ -85,6 +85,7 @@
         '<(mozc_oss_src_dir)/base/absl.gyp:absl_strings',
         '<(mozc_oss_src_dir)/base/absl.gyp:absl_time',
         '<(mozc_oss_src_dir)/base/base.gyp:base',
+        '<(mozc_oss_src_dir)/base/base.gyp:base_core',
         '<(mozc_oss_src_dir)/base/base.gyp:config_file_stream',
         '<(mozc_oss_src_dir)/base/base.gyp:serialized_string_array',
         '<(mozc_oss_src_dir)/base/base.gyp:version',

src/session/session_handler_scenario_test.cc

@@ -146,6 +146,7 @@ const char *kScenarioFileList[] = {
     DATA_DIR "segment_focus.txt",
     DATA_DIR "segment_width.txt",
     DATA_DIR "suggest_after_zero_query.txt",
+    DATA_DIR "t13n_negative_number.txt",
     DATA_DIR "toggle_flick_hiragana_preedit_a.txt",
     DATA_DIR "toggle_flick_hiragana_preedit_ka.txt",
     DATA_DIR "toggle_flick_hiragana_preedit_sa.txt",