Find range of SVN commits where a file matches a pattern

svn-range-finder.sh

#!/bin/bash
# GENERATED BY GEMINI

# Configuration Variables
# The path to the file in the SVN repository
FILE_PATH="src/library/parallel/NAMESPACE"
# The pattern you are searching for (case-sensitive)
SEARCH_PATTERN="splitList"

# --- Script Logic ---

echo "--- SVN Commit Range Finder ---"
echo "File: $FILE_PATH"
echo "Pattern: $SEARCH_PATTERN"
echo ""

# Function to get the commit date (YYYY-MM-DD HH:MM:SS +/-TZ) for a given revision.
# It relies on the standard svn log output format.
get_commit_date() {
    local rev=$1
    # svn log -r REV --limit 1 fetches the specific log entry for the revision.
    # We filter for the line starting with 'r' and extract the date/time fields (usually fields 5, 6, 7).
    svn log -r "$rev" --limit 1 "$FILE_PATH" 2>/dev/null | \
        grep -E '^r[0-9]+' | awk '{print $5, $6, $7}'
}


# 0. Check if the file is even under Subversion control (not just a local file).
SVN_STATUS=$(svn info "$FILE_PATH" 2>&1)
SVN_INFO_EXIT_CODE=$?

if [ "$SVN_INFO_EXIT_CODE" -ne 0 ]; then
    echo "Error: The file '$FILE_PATH' is likely not under Subversion control at this path,"
    echo "       or you are not running this script from within an SVN working copy."
    echo "       svn info failed with: $(echo "$SVN_STATUS" | head -n 1)"
    echo "       Please ensure the file has been committed at least once and the path is correct."
    exit 1
fi

# 1. Fetch all revision numbers that affected the file path.
# Using the fixed -r option.
REVS_LOG=$(svn log --quiet -r 1:HEAD "$FILE_PATH" 2>&1)
LOG_EXIT_CODE=$?

if [ "$LOG_EXIT_CODE" -ne 0 ]; then
    echo "Error: svn log failed for '$FILE_PATH'."
    echo "       SVN reported: $REVS_LOG"
    exit 1
fi

# Filter the log output to get revision numbers.
REVS=$(echo "$REVS_LOG" | grep -E '^r[0-9]+' | awk '{print $1}' | sed 's/r//g' | sort -n)

if [ -z "$REVS" ]; then
    echo "Error: Could not find any history (commits) for file $FILE_PATH. It may be a newly added file awaiting its first commit."
    exit 1
fi

FIRST_MATCH=""
LAST_MATCH=""
MATCH_COUNT=0

# 2. Iterate through relevant revisions and check the file content.
echo "Scanning $(echo $REVS | wc -w) historical revisions..."

for REV in $REVS; do
    # Use svn cat -r to get the file content at this specific revision.
    if svn cat -r $REV "$FILE_PATH" 2>/dev/null | grep -q "$SEARCH_PATTERN"; then
        if [ -z "$FIRST_MATCH" ]; then
            FIRST_MATCH=$REV
        fi
        LAST_MATCH=$REV
        MATCH_COUNT=$((MATCH_COUNT + 1))
    fi
done

# 3. Report the findings.
echo ""
if [ "$MATCH_COUNT" -gt 0 ]; then
    # Fetch the dates for the boundary revisions
    FIRST_DATE=$(get_commit_date $FIRST_MATCH)
    LAST_DATE=$(get_commit_date $LAST_MATCH)

    echo "SUCCESS: Found '$SEARCH_PATTERN' in $MATCH_COUNT unique revisions."
    echo "The pattern was present in the overall commit range:"
    echo "  First Match: r$FIRST_MATCH ($FIRST_DATE)"
    echo "  Last Match: r$LAST_MATCH ($LAST_DATE)"
    echo ""
    echo "This means the line has existed (at least intermittently) since commit r$FIRST_MATCH up to r$LAST_MATCH."
else
    echo "RESULT: Pattern '$SEARCH_PATTERN' was NOT found in any revision of $FILE_PATH."
fi

# To use this script:
# 1. Save it as svn-range-finder.sh
# 2. Make it executable: chmod +x svn-range-finder.sh
# 3. Run it from inside a working copy or a location with SVN access.