lint: Fix lint-whitespace issues

2 files changed, 81 insertions, 136 deletions

diff --git a/test/lint/lint-whitespace.py b/test/lint/lint-whitespace.py
deleted file mode 100755
index f5e4a776d0..0000000000
--- a/test/lint/lint-whitespace.py
+++ /dev/null
@@ -1,136 +0,0 @@
-#!/usr/bin/env python3
-#
-# Copyright (c) 2017-2022 The Bitcoin Core developers
-# Distributed under the MIT software license, see the accompanying
-# file COPYING or http://www.opensource.org/licenses/mit-license.php.
-#
-# Check for new lines in diff that introduce trailing whitespace or
-# tab characters instead of spaces.
-
-# We can't run this check unless we know the commit range for the PR.
-
-import argparse
-import os
-import re
-import sys
-
-from subprocess import check_output
-
-EXCLUDED_DIRS = ["depends/patches/",
-                 "contrib/guix/patches/",
-                 "src/leveldb/",
-                 "src/crc32c/",
-                 "src/secp256k1/",
-                 "src/minisketch/",
-                 "doc/release-notes/",
-                 "src/qt/locale"]
-
-def parse_args():
-    """Parse command line arguments."""
-    parser = argparse.ArgumentParser(
-        description="""
-            Check for new lines in diff that introduce trailing whitespace
-            or tab characters instead of spaces in unstaged changes, the
-            previous n commits, or a commit-range.
-        """,
-        epilog=f"""
-            You can manually set the commit-range with the COMMIT_RANGE
-            environment variable (e.g. "COMMIT_RANGE='47ba2c3...ee50c9e'
-            {sys.argv[0]}"). Defaults to current merge base when neither
-            prev-commits nor the environment variable is set.
-        """)
-
-    parser.add_argument("--prev-commits", "-p", required=False, help="The previous n commits to check")
-
-    return parser.parse_args()
-
-
-def report_diff(selection):
-    filename = ""
-    seen = False
-    seenln = False
-
-    print("The following changes were suspected:")
-
-    for line in selection:
-        if re.match(r"^diff", line):
-            filename = line
-            seen = False
-        elif re.match(r"^@@", line):
-            linenumber = line
-            seenln = False
-        else:
-            if not seen:
-                # The first time a file is seen with trailing whitespace or a tab character, we print the
-                # filename (preceded by a newline).
-                print("")
-                print(filename)
-                seen = True
-            if not seenln:
-                print(linenumber)
-                seenln = True
-            print(line)
-
-
-def get_diff(commit_range, check_only_code):
-    exclude_args = [":(exclude)" + dir for dir in EXCLUDED_DIRS]
-
-    if check_only_code:
-        what_files = ["*.cpp", "*.h", "*.md", "*.py", "*.sh"]
-    else:
-        what_files = ["."]
-
-    diff = check_output(["git", "diff", "-U0", commit_range, "--"] + what_files + exclude_args, text=True, encoding="utf8")
-
-    return diff
-
-
-def main():
-    args = parse_args()
-
-    if not os.getenv("COMMIT_RANGE"):
-        if args.prev_commits:
-            commit_range = "HEAD~" + args.prev_commits + "...HEAD"
-        else:
-            # This assumes that the target branch of the pull request will be master.
-            merge_base = check_output(["git", "merge-base", "HEAD", "master"], text=True, encoding="utf8").rstrip("\n")
-            commit_range = merge_base + "..HEAD"
-    else:
-        commit_range = os.getenv("COMMIT_RANGE")
-        if commit_range == "SKIP_EMPTY_NOT_A_PR":
-            sys.exit(0)
-
-    whitespace_selection = []
-    tab_selection = []
-
-    # Check if trailing whitespace was found in the diff.
-    for line in get_diff(commit_range, check_only_code=False).splitlines():
-        if re.match(r"^(diff --git|\@@|^\+.*\s+$)", line):
-            whitespace_selection.append(line)
-
-    whitespace_additions = [i for i in whitespace_selection if i.startswith("+")]
-
-    # Check if tab characters were found in the diff.
-    for line in get_diff(commit_range, check_only_code=True).splitlines():
-        if re.match(r"^(diff --git|\@@|^\+.*\t)", line):
-            tab_selection.append(line)
-
-    tab_additions = [i for i in tab_selection if i.startswith("+")]
-
-    ret = 0
-
-    if len(whitespace_additions) > 0:
-        print("This diff appears to have added new lines with trailing whitespace.")
-        report_diff(whitespace_selection)
-        ret = 1
-
-    if len(tab_additions) > 0:
-        print("This diff appears to have added new lines with tab characters instead of spaces.")
-        report_diff(tab_selection)
-        ret = 1
-
-    sys.exit(ret)
-
-
-if __name__ == "__main__":
-    main()
diff --git a/test/lint/test_runner/src/main.rs b/test/lint/test_runner/src/main.rs
index b97e822484..f9df576239 100644
--- a/test/lint/test_runner/src/main.rs
+++ b/test/lint/test_runner/src/main.rs
@@ -95,6 +95,85 @@ fs:: namespace, which has unsafe filesystem functions marked as deleted.
     }
 }
 
+/// Return the pathspecs for whitespace related excludes
+fn get_pathspecs_exclude_whitespace() -> Vec<String> {
+    let mut list = get_pathspecs_exclude_subtrees();
+    list.extend(
+        [
+            // Permanent excludes
+            "*.patch",
+            "src/qt/locale",
+            "contrib/windeploy/win-codesign.cert",
+            "doc/README_windows.txt",
+            // Temporary excludes, or existing violations
+            "doc/release-notes/release-notes-0.*",
+            "contrib/init/bitcoind.openrc",
+            "contrib/macdeploy/macdeployqtplus",
+            "src/crypto/sha256_sse4.cpp",
+            "src/qt/res/src/*.svg",
+            "test/functional/test_framework/crypto/ellswift_decode_test_vectors.csv",
+            "test/functional/test_framework/crypto/xswiftec_inv_test_vectors.csv",
+            "contrib/qos/tc.sh",
+            "contrib/verify-commits/gpg.sh",
+            "src/univalue/include/univalue_escapes.h",
+            "src/univalue/test/object.cpp",
+            "test/lint/git-subtree-check.sh",
+        ]
+        .iter()
+        .map(|s| format!(":(exclude){}", s)),
+    );
+    list
+}
+
+fn lint_trailing_whitespace() -> LintResult {
+    let trailing_space = git()
+        .args(["grep", "-I", "--line-number", "\\s$", "--"])
+        .args(get_pathspecs_exclude_whitespace())
+        .status()
+        .expect("command error")
+        .success();
+    if trailing_space {
+        Err(r#"
+^^^
+Trailing whitespace is problematic, because git may warn about it, or editors may remove it by
+default, forcing developers in the future to either undo the changes manually or spend time on
+review.
+
+Thus, it is best to remove the trailing space now.
+
+Please add any false positives, such as subtrees, Windows-related files, patch files, or externally
+sourced files to the exclude list.
+            "#
+        .to_string())
+    } else {
+        Ok(())
+    }
+}
+
+fn lint_tabs_whitespace() -> LintResult {
+    let tabs = git()
+        .args(["grep", "-I", "--line-number", "--perl-regexp", "^\\t", "--"])
+        .args(["*.cpp", "*.h", "*.md", "*.py", "*.sh"])
+        .args(get_pathspecs_exclude_whitespace())
+        .status()
+        .expect("command error")
+        .success();
+    if tabs {
+        Err(r#"
+^^^
+Use of tabs in this codebase is problematic, because existing code uses spaces and tabs will cause
+display issues and conflict with editor settings.
+
+Please remove the tabs.
+
+Please add any false positives, such as subtrees, or externally sourced files to the exclude list.
+            "#
+        .to_string())
+    } else {
+        Ok(())
+    }
+}
+
 fn lint_includes_build_config() -> LintResult {
     let config_path = "./src/config/bitcoin-config.h.in";
     let include_directive = "#include <config/bitcoin-config.h>";
@@ -232,6 +311,8 @@ fn main() -> ExitCode {
     let test_list: Vec<(&str, LintFn)> = vec![
         ("subtree check", lint_subtree),
         ("std::filesystem check", lint_std_filesystem),
+        ("trailing whitespace check", lint_trailing_whitespace),
+        ("no-tabs check", lint_tabs_whitespace),
         ("build config includes check", lint_includes_build_config),
         ("-help=1 documentation check", lint_doc),
         ("lint-*.py scripts", lint_all),