PR Cycle Time Analysis - Measures time from first Claude Code prompt to PR merge (Next-gen DORA metric)

pr-cycle-time.sh

#!/bin/bash
# PR Cycle Time Analysis - Measures time from first Claude prompt to PR merge
# Groups by CALENDAR WEEK (Mon-Sun) when PR merged
# "Next gen DORA" - captures full ideation-to-ship cycle via Claude sessions

set -euo pipefail

WEEKS_AGO="${1:-0}"  # 0 = current week, 1 = last week, etc.
REPO_FILTER="${2:-}"
CLAUDE_DIR="$HOME/.claude"

# Calculate calendar week boundaries (Monday-Sunday)
# Get the Monday of the target week
get_monday() {
    local weeks_back=$1
    local today_dow=$(date +%u)  # 1=Mon, 7=Sun
    local days_since_monday=$((today_dow - 1))
    local days_back=$((days_since_monday + (weeks_back * 7)))
    date -v-${days_back}d +%Y-%m-%d 2>/dev/null || date -d "-${days_back} days" +%Y-%m-%d
}

# Get the Sunday of the target week (Monday + 6 days)
get_sunday() {
    local monday=$1
    # macOS: use -v to add days, need to set base date first then adjust
    local monday_epoch=$(date -j -f "%Y-%m-%d" "$monday" +%s 2>/dev/null)
    if [ -n "$monday_epoch" ]; then
        local sunday_epoch=$((monday_epoch + 6*86400))
        date -r "$sunday_epoch" +%Y-%m-%d
    else
        date -d "$monday + 6 days" +%Y-%m-%d
    fi
}

# Get ISO week number
get_week_number() {
    local date_str=$1
    date -j -f "%Y-%m-%d" "$date_str" +%V 2>/dev/null || date -d "$date_str" +%V
}

WEEK_MONDAY=$(get_monday "$WEEKS_AGO")
WEEK_SUNDAY=$(get_sunday "$WEEK_MONDAY")
WEEK_NUM=$(get_week_number "$WEEK_MONDAY")

# Format for display
WEEK_START_DISPLAY=$(date -j -f "%Y-%m-%d" "$WEEK_MONDAY" "+%b %d" 2>/dev/null || date -d "$WEEK_MONDAY" "+%b %d")
WEEK_END_DISPLAY=$(date -j -f "%Y-%m-%d" "$WEEK_SUNDAY" "+%b %d" 2>/dev/null || date -d "$WEEK_SUNDAY" "+%b %d")

# Convert to timestamps for filtering
CUTOFF_TS=$(date -j -f "%Y-%m-%d" "$WEEK_MONDAY" +%s 2>/dev/null || date -d "$WEEK_MONDAY" +%s)
END_TS=$(date -j -f "%Y-%m-%dT%H:%M:%S" "${WEEK_SUNDAY}T23:59:59" +%s 2>/dev/null || date -d "${WEEK_SUNDAY} 23:59:59" +%s)

# Temp files for processing
TEMP_DIR=$(mktemp -d)
trap "rm -rf $TEMP_DIR" EXIT

PR_DATA="$TEMP_DIR/pr_data.tsv"
MERGED_DATA="$TEMP_DIR/merged_data.tsv"

echo "Scanning Claude sessions for PRs..." >&2

# Find all session JSONL files with PR URLs (no date filtering - we filter by merge date later)
find "$CLAUDE_DIR/projects" -name "*.jsonl" -type f 2>/dev/null | while read -r session_file; do
    # Check if file contains GitHub PR URLs
    if grep -q 'github\.com/[^/"[:space:]]*/[^/"[:space:]]*/pull/[0-9]' "$session_file" 2>/dev/null; then
        # Get first message timestamp from session (skip non-message entries like file-history-snapshot)
        first_ts=$(grep -m1 '"type":"user"\|"type":"assistant"' "$session_file" 2>/dev/null | jq -r '.timestamp // empty' 2>/dev/null)

        if [ -z "$first_ts" ]; then
            continue
        fi

        # Convert to unix timestamp
        first_unix=$(date -j -f "%Y-%m-%dT%H:%M:%S" "${first_ts%%.*}" +%s 2>/dev/null || \
                     date -d "${first_ts%%.*}" +%s 2>/dev/null || echo "0")

        # Extract PR URLs from this session
        grep -oh 'https://github\.com/[^/"[:space:]]*/[^/"[:space:]]*/pull/[0-9]*' "$session_file" 2>/dev/null | \
            sort -u | while read -r pr_url; do
                # Parse owner/repo/number from URL
                if [[ "$pr_url" =~ github\.com/([^/]+)/([^/]+)/pull/([0-9]+) ]]; then
                    owner="${BASH_REMATCH[1]}"
                    repo="${BASH_REMATCH[2]}"
                    pr_num="${BASH_REMATCH[3]}"

                    # Apply repo filter if specified
                    if [ -n "$REPO_FILTER" ] && [[ "$owner/$repo" != *"$REPO_FILTER"* ]]; then
                        continue
                    fi

                    echo -e "${owner}/${repo}\t${pr_num}\t${first_ts}\t${first_unix}"
                fi
            done
    fi
done | sort -t$'\t' -k1,2 -k4,4n | awk -F'\t' '!seen[$1"\t"$2]++' > "$PR_DATA"
# ^ Sort by repo/PR then by timestamp, keep earliest session per PR

# Count unique PRs
PR_COUNT=$(wc -l < "$PR_DATA" | tr -d ' ')

if [ "$PR_COUNT" -eq 0 ]; then
    echo "## PR Cycle Time - CW$WEEK_NUM ($WEEK_START_DISPLAY - $WEEK_END_DISPLAY)"
    echo ""
    echo "No PRs found in Claude sessions."
    exit 0
fi

echo "Found $PR_COUNT unique PRs, querying GitHub..." >&2

# Query GitHub for merge status and filter by merge date
MERGED_COUNT=0
OPEN_COUNT=0
TOTAL_CHECKED=0

while IFS=$'\t' read -r repo pr_num session_ts session_unix; do
    TOTAL_CHECKED=$((TOTAL_CHECKED + 1))

    # Progress indicator every 20 PRs
    if [ $((TOTAL_CHECKED % 20)) -eq 0 ]; then
        echo "  Checked $TOTAL_CHECKED / $PR_COUNT PRs..." >&2
    fi

    # Query GitHub
    gh_result=$(gh pr view "$pr_num" --repo "$repo" --json mergedAt,state,number,title 2>/dev/null || echo '{"state":"error"}')

    state=$(echo "$gh_result" | jq -r '.state // "error"')
    merged_at=$(echo "$gh_result" | jq -r '.mergedAt // empty')
    title=$(echo "$gh_result" | jq -r '.title // "Unknown"' | cut -c1-50)

    if [ "$state" = "MERGED" ] && [ -n "$merged_at" ]; then
        # Convert merge timestamp
        merged_unix=$(date -j -f "%Y-%m-%dT%H:%M:%SZ" "$merged_at" +%s 2>/dev/null || \
                      date -d "$merged_at" +%s 2>/dev/null || echo "0")

        # Filter by MERGE DATE being within calendar week
        if [ "$merged_unix" -ge "$CUTOFF_TS" ] && [ "$merged_unix" -le "$END_TS" ]; then
            if [ "$merged_unix" -gt "$session_unix" ]; then
                cycle_secs=$((merged_unix - session_unix))
                cycle_mins=$((cycle_secs / 60))

                echo -e "${repo}\t${pr_num}\t${cycle_mins}\t${merged_at}\t${title}" >> "$MERGED_DATA"
                MERGED_COUNT=$((MERGED_COUNT + 1))
            fi
        fi
    elif [ "$state" = "OPEN" ]; then
        OPEN_COUNT=$((OPEN_COUNT + 1))
    fi
done < "$PR_DATA"

echo "Done." >&2

# Calculate statistics if we have merged PRs
if [ ! -f "$MERGED_DATA" ] || [ ! -s "$MERGED_DATA" ]; then
    echo "## PR Cycle Time - CW$WEEK_NUM ($WEEK_START_DISPLAY - $WEEK_END_DISPLAY)"
    echo ""
    echo "_Measures: first Claude prompt → PR merge (Claude-assisted PRs only)_"
    echo ""
    echo "| Metric | Value |"
    echo "|--------|-------|"
    echo "| PRs in Claude sessions | $PR_COUNT |"
    echo "| Merged this week | 0 |"
    echo "| Currently open | $OPEN_COUNT |"
    echo ""
    echo "No PRs merged during this calendar week."
    exit 0
fi

# Calculate repo breakdown
REPO_BREAKDOWN="$TEMP_DIR/repo_breakdown.txt"
cut -f1 "$MERGED_DATA" | sort | uniq -c | sort -rn > "$REPO_BREAKDOWN"

# Calculate statistics
SORTED_TIMES="$TEMP_DIR/sorted_times.txt"
cut -f3 "$MERGED_DATA" | sort -n > "$SORTED_TIMES"

STATS=$(awk '
BEGIN { sum=0; count=0; min=999999; max=0 }
{
    mins = $1
    count++
    sum += mins
    if (mins < min) min = mins
    if (mins > max) max = mins
}
END {
    avg = (count > 0) ? int(sum/count) : 0
    printf "%d\t%d\t%d\t%d\n", count, avg, min, max
}
' "$SORTED_TIMES")

# Calculate median from sorted file
TOTAL_LINES=$(wc -l < "$SORTED_TIMES" | tr -d ' ')
if [ "$TOTAL_LINES" -gt 0 ]; then
    MEDIAN_LINE=$(( (TOTAL_LINES + 1) / 2 ))
    MEDIAN=$(sed -n "${MEDIAN_LINE}p" "$SORTED_TIMES")
else
    MEDIAN=0
fi

COUNT=$(echo "$STATS" | cut -f1)
AVG=$(echo "$STATS" | cut -f2)
MIN=$(echo "$STATS" | cut -f3)
MAX=$(echo "$STATS" | cut -f4)

# Format times for display
format_time() {
    local mins=$1
    if [ "$mins" -lt 60 ]; then
        echo "${mins}m"
    elif [ "$mins" -lt 1440 ]; then
        local hours=$((mins / 60))
        local rem=$((mins % 60))
        if [ "$rem" -gt 0 ]; then
            echo "${hours}h ${rem}m"
        else
            echo "${hours}h"
        fi
    else
        local days=$((mins / 1440))
        local hours=$(((mins % 1440) / 60))
        echo "${days}d ${hours}h"
    fi
}

# Distribution buckets
DIST=$(awk -F'\t' '
{
    mins = $3
    if (mins < 15) b1++
    else if (mins < 30) b2++
    else if (mins < 60) b3++
    else if (mins < 120) b4++
    else b5++
}
END {
    printf "%d\t%d\t%d\t%d\t%d\n", b1+0, b2+0, b3+0, b4+0, b5+0
}
' "$MERGED_DATA")

B1=$(echo "$DIST" | cut -f1)
B2=$(echo "$DIST" | cut -f2)
B3=$(echo "$DIST" | cut -f3)
B4=$(echo "$DIST" | cut -f4)
B5=$(echo "$DIST" | cut -f5)

# Generate bar for distribution
make_bar() {
    local count=$1
    local max_count=$2
    local max_width=20

    if [ "$max_count" -eq 0 ]; then
        echo ""
        return
    fi

    local width=$((count * max_width / max_count))
    printf '%*s' "$width" '' | tr ' ' '█'
}

MAX_BUCKET=$(echo "$B1 $B2 $B3 $B4 $B5" | tr ' ' '\n' | sort -rn | head -1)

# Output report
echo "## PR Cycle Time - CW$WEEK_NUM ($WEEK_START_DISPLAY - $WEEK_END_DISPLAY)"
echo ""
echo "| Metric | Value |"
echo "|--------|-------|"
echo "| Merged (with Claude sessions) | $MERGED_COUNT |"
echo "| Avg cycle time | $(format_time $AVG) |"
echo "| Median cycle time | $(format_time $MEDIAN) |"
echo "| Fastest | $(format_time $MIN) |"
echo "| Slowest | $(format_time $MAX) |"
echo ""

# Repo breakdown
echo "## By Repo"
echo ""
while read -r count repo; do
    short_repo=$(echo "$repo" | cut -d'/' -f2)
    echo "- $short_repo: $count"
done < "$REPO_BREAKDOWN"
echo ""

echo "## Distribution"
echo ""
printf "< 15 mins  %s %d\n" "$(make_bar $B1 $MAX_BUCKET)" "$B1"
printf "15-30 mins %s %d\n" "$(make_bar $B2 $MAX_BUCKET)" "$B2"
printf "30-60 mins %s %d\n" "$(make_bar $B3 $MAX_BUCKET)" "$B3"
printf "1-2 hours  %s %d\n" "$(make_bar $B4 $MAX_BUCKET)" "$B4"
printf "2+ hours   %s %d\n" "$(make_bar $B5 $MAX_BUCKET)" "$B5"
echo ""
echo "## Recent PRs"
echo ""

# Show recent merged PRs (sorted by merge date, newest first)
sort -t$'\t' -k4 -r "$MERGED_DATA" | head -10 | while IFS=$'\t' read -r repo pr_num cycle_mins merged_at title; do
    # Format merge date
    merge_date=$(date -j -f "%Y-%m-%dT%H:%M:%SZ" "$merged_at" "+%b %d" 2>/dev/null || \
                 date -d "$merged_at" "+%b %d" 2>/dev/null || echo "recent")

    # Get short repo name
    short_repo=$(echo "$repo" | cut -d'/' -f2)

    echo "- ${short_repo}#${pr_num}: $(format_time $cycle_mins) (merged $merge_date)"
done

echo ""
echo "---"
echo "_Cycle time = first Claude prompt → PR merge. Only includes PRs found in local ~/.claude session logs._"