GH-48673: [C++] Fix ToStringWithoutContextLines to check for :\d+ pattern before removing lines (#48674)

### Rationale for this change

This PR proposes to fix the todo https://github.com/apache/arrow/blob/7ebc88c8fae62ed97bc30865c845c8061132af7e/cpp/src/arrow/status.cc#L131-L134 which would allows a better parsing for line numbers.

I could not find the relevant example to demonstrate within this project but assume that we have a test such as:

(Generated by ChatGPT)

```cpp
TEST(BlockParser, ErrorMessageWithColonsPreserved) {
  Status st(StatusCode::Invalid,
            "CSV parse error: Row #2: Expected 2 columns, got 3: 12:34:56,key:value,data\n"
            "Error details: Time format: 12:34:56, Key: value\n"
            "parser_test.cc:940  Parse(parser, csv, &out_size)");

  std::string expected_msg =
      "Invalid: CSV parse error: Row #2: Expected 2 columns, got 3: 12:34:56,key:value,data\n"
      "Error details: Time format: 12:34:56, Key: value";

  ASSERT_RAISES_WITH_MESSAGE(Invalid, expected_msg, st);
}

// Test with URL-like data (another common case with colons)
TEST(BlockParser, ErrorMessageWithURLPreserved) {
  Status st(StatusCode::Invalid,
            "CSV parse error: Row #2: Expected 1 columns, got 2: http://arrow.apache.org:8080/api,data\n"
            "URL: http://arrow.apache.org:8080/api\n"
            "parser_test.cc:974  Parse(parser, csv, &out_size)");

  std::string expected_msg =
      "Invalid: CSV parse error: Row #2: Expected 1 columns, got 2: http://arrow.apache.org:8080/api,data\n"
      "URL: http://arrow.apache.org:8080/api";

  ASSERT_RAISES_WITH_MESSAGE(Invalid, expected_msg, st);
}
```

then it fails.

### What changes are included in this PR?

Fixed `Status::ToStringWithoutContextLines()` to only remove context lines matching the `filename:line` pattern (`:\d+`), preventing legitimate error messages containing colons from being incorrectly stripped.

### Are these changes tested?

Manually tested, and unittests were added, with `cmake .. --preset ninja-debug -DARROW_EXTRA_ERROR_CONTEXT=ON`.

### Are there any user-facing changes?

No, test-only.

* GitHub Issue: #48673

Authored-by: Hyukjin Kwon <[email protected]>
Signed-off-by: Sutou Kouhei <[email protected]>

Author: HyukjinKwon

cpp/src/arrow/status.cc

@@ -13,6 +13,7 @@
 #include "arrow/status.h"
 
 #include <cassert>
+#include <cctype>
 #include <cstdlib>
 #include <iostream>
 #ifdef ARROW_EXTRA_ERROR_CONTEXT
@@ -131,8 +132,25 @@ std::string Status::ToStringWithoutContextLines() const {
     if (last_new_line_position == std::string::npos) {
       break;
     }
-    // TODO: We may want to check /:\d+ /
-    if (message.find(":", last_new_line_position) == std::string::npos) {
+    // Check for the pattern ":\d+ " (colon followed by one or more digits and a space)
+    // to identify context lines in the format "filename:line  expr"
+    auto colon_position = message.find(":", last_new_line_position);
+    if (colon_position == std::string::npos) {
+      break;
+    }
+    // Verify that the colon is followed by one or more digits and then a space
+    size_t pos = colon_position + 1;
+    if (pos >= message.size() ||
+        !std::isdigit(static_cast<unsigned char>(message[pos]))) {
+      break;
+    }
+    // Skip all digits
+    while (pos < message.size() &&
+           std::isdigit(static_cast<unsigned char>(message[pos]))) {
+      pos++;
+    }
+    // Check if followed by a space
+    if (pos >= message.size() || message[pos] != ' ') {
       break;
     }
     message = message.substr(0, last_new_line_position);

cpp/src/arrow/status_test.cc

@@ -342,4 +342,21 @@ TEST(StatusTest, ReturnIfNotOk) {
   ASSERT_EQ(StripContext(st.message()), "StatusLike: 43");
 }
 
+#ifdef ARROW_EXTRA_ERROR_CONTEXT
+TEST(StatusTest, ToStringWithoutContextLines) {
+  Status status = Status::IOError("base error");
+  status.AddContextLine("file1.cc", 42, "expr");
+  status.AddContextLine("file2.cc", 100, "expr");
+
+  ASSERT_EQ(status.ToStringWithoutContextLines(), "IOError: base error");
+
+  Status status2(StatusCode::Invalid,
+                 "Error message\nThis line has: a colon but no digits");
+  status2.AddContextLine("file.cc", 20, "expr");
+
+  ASSERT_EQ(status2.ToStringWithoutContextLines(),
+            "Invalid: Error message\nThis line has: a colon but no digits");
+}
+#endif
+
 }  // namespace arrow