Git - Command Reference H-R

# Create blob object from file
git hash-object file.txt
git hash-object -w file.txt        # Write to object database

# Create object from stdin
echo "Hello World" | git hash-object --stdin
echo "Hello World" | git hash-object -w --stdin

# Specify object type
git hash-object -t blob file.txt

# Get help for commands
git help
git help add                    # Detailed help for 'add'
git help -a                     # List all commands
git help -g                     # List concept guides

# Quick help
git add -h                      # Short usage summary
git commit --help               # Same as 'git help commit'

# Web help (opens in browser)
git help -w add

# Initialize repository
git init                        # Current directory
git init my-project             # New directory
git init --bare                 # Bare repository (no working directory)

# Initialize with specific branch name
git init -b main
git init --initial-branch=main

# Initialize with template
git init --template=/path/to/template

# Reinitialize existing repository
git init                        # Safe to run in existing repo

# Basic log
git log
git log --oneline               # Compact format
git log -5                      # Last 5 commits
git log --graph                 # ASCII graph

# Formatting
git log --pretty=format:"%h %s" 
git log --pretty=oneline
git log --pretty=short
git log --pretty=full

# Filter by author/date
git log --author="John Doe"
git log --since="2 weeks ago"
git log --until="2023-01-01"
git log --grep="bug fix"

# File history
git log -- file.txt            # Commits affecting file
git log --follow file.txt      # Follow renames
git log -p file.txt             # Show patches

# Branch specific
git log main..feature           # Commits in feature not in main
git log --all                   # All branches
git log --branches              # All local branches

# Advanced options
git log --stat                  # Show file statistics
git log --shortstat             # Condensed stats
git log --name-only             # File names only
git log --name-status           # File names with status

# Merge commits
git log --merges                # Merge commits only
git log --no-merges             # Exclude merge commits
git log --first-parent          # Follow first parent only

# List tracked files
git ls-files
git ls-files -s                 # Show staging info
git ls-files -c                 # Show cached files

# Show different file states
git ls-files -d                 # Deleted files
git ls-files -m                 # Modified files
git ls-files -o                 # Other (untracked) files
git ls-files -u                 # Unmerged files

# Ignore patterns
git ls-files --exclude-standard # Apply .gitignore rules
git ls-files --others --ignored --exclude-standard

# Filter by patterns
git ls-files "*.js"
git ls-files --directory

# List remote references
git ls-remote origin
git ls-remote --heads origin    # Branches only
git ls-remote --tags origin     # Tags only

# Check specific refs
git ls-remote origin main
git ls-remote origin refs/heads/main

# List all remotes
git ls-remote --exit-code origin  # Exit code indicates if remote exists

# List tree contents
git ls-tree HEAD
git ls-tree -r HEAD             # Recursive
git ls-tree --name-only HEAD    # Names only

# List specific tree
git ls-tree HEAD~1
git ls-tree v1.0

# Show specific directory
git ls-tree HEAD src/

# Basic merge
git merge feature-branch
git merge origin/main

# Merge strategies
git merge --no-ff feature-branch    # Always create merge commit
git merge --ff-only feature-branch  # Fast-forward only
git merge --squash feature-branch   # Squash commits

# Merge with message
git merge -m "Merge feature" feature-branch

# Merge strategies (advanced)
git merge -s recursive feature-branch
git merge -s ours feature-branch    # Ignore their changes
git merge -s octopus branch1 branch2 branch3

# Strategy options
git merge -X ours feature-branch    # Prefer our changes in conflicts
git merge -X theirs feature-branch  # Prefer their changes

# Abort merge
git merge --abort

# Continue merge after resolving conflicts
git merge --continue

# Find merge base
git merge-base main feature
git merge-base --all main feature   # All merge bases

# Check if ancestor
git merge-base --is-ancestor main feature
echo $?  # 0 if main is ancestor of feature

# Fork point
git merge-base --fork-point main feature

# Launch merge tool
git mergetool
git mergetool file.txt           # Specific file

# Use specific tool
git mergetool --tool=vimdiff
git mergetool -t kdiff3

# Configure merge tool
git config merge.tool vimdiff
git config mergetool.vimdiff.cmd 'vimdiff "$LOCAL" "$MERGED" "$REMOTE"'

# Rename file
git mv old-name.txt new-name.txt

# Move file to directory
git mv file.txt directory/

# Move directory
git mv old-dir/ new-dir/

# Multiple files
git mv *.txt docs/

# Find name for commit
git name-rev HEAD
git name-rev abc1234

# Options
git name-rev --tags HEAD         # Use tags only
git name-rev --all               # All refs
git name-rev --stdin             # Read from stdin

# Add note to commit
git notes add -m "Important fix" HEAD
git notes add -m "Note" abc1234

# Show notes
git notes show HEAD
git notes list

# Edit note
git notes edit HEAD

# Remove note
git notes remove HEAD

# Different note namespaces
git notes --ref=bugs add -m "Bug report" HEAD
git notes --ref=bugs show HEAD

# Create pack file (low-level)
git rev-list --objects --all | git pack-objects pack

# Create pack with specific objects
echo "HEAD" | git pack-objects --stdout > pack.pack

# Prune unreachable objects
git prune
git prune --dry-run              # Show what would be pruned
git prune --expire=1.week.ago    # Prune objects older than 1 week

# Prune with verbose output
git prune -v

# Basic pull
git pull                         # Default remote and branch
git pull origin main             # Specific remote and branch

# Pull with rebase
git pull --rebase
git pull --rebase origin main

# Pull all remotes
git pull --all

# Pull with specific strategy
git pull --no-ff                # Always create merge commit
git pull --ff-only              # Fast-forward only

# Shallow pull
git pull --depth=1

# Pull with submodules
git pull --recurse-submodules

# Basic push
git push                         # Default remote and branch
git push origin main             # Specific remote and branch

# Push all branches
git push --all origin
git push --mirror origin        # Mirror (including refs)

# Push tags
git push --tags origin
git push origin v1.0             # Specific tag

# Set upstream
git push -u origin feature      # Set upstream tracking
git push --set-upstream origin feature

# Force push (dangerous)
git push --force origin main
git push --force-with-lease origin main  # Safer force push

# Delete remote branch/tag
git push origin --delete feature-branch
git push origin --delete tag v1.0
git push origin :feature-branch # Alternative syntax

# Push to multiple remotes
git push origin main
git push backup main

# Dry run
git push --dry-run origin main

# Compare ranges (Git 2.19+)
git range-diff main~3..main~1 feature~3..feature~1
git range-diff main...main-new feature...feature-new

# Read tree into index (low-level)
git read-tree HEAD
git read-tree --reset HEAD      # Reset index to match tree

# Three-way read
git read-tree -m HEAD~1 HEAD~1 HEAD

# Basic rebase
git rebase main                  # Rebase current branch onto main
git rebase main feature          # Rebase feature onto main

# Interactive rebase
git rebase -i HEAD~3             # Edit last 3 commits
git rebase -i main               # Interactive rebase onto main

# Rebase onto different base
git rebase --onto main server client

# Continue/abort rebase
git rebase --continue            # After resolving conflicts
git rebase --skip                # Skip current commit
git rebase --abort               # Abort rebase

# Rebase options
git rebase --preserve-merges main   # Keep merge structure
git rebase --rebase-merges main     # Recreate merge structure
git rebase --autosquash main        # Auto-squash fixup commits

# Strategy options
git rebase -X ours main          # Prefer our changes in conflicts
git rebase -X theirs main        # Prefer their changes

# Show reflog
git reflog                       # Current branch reflog
git reflog HEAD                  # HEAD reflog
git reflog main                  # Specific branch reflog

# Show all reflogs
git reflog --all

# Reflog with dates
git reflog --date=iso
git reflog --date=relative

# Expire reflog entries
git reflog expire --expire=30.days --all
git reflog delete HEAD@{5}      # Delete specific entry

# Reflog for specific branch
git reflog show main

# List remotes
git remote                       # Remote names
git remote -v                    # Remote names with URLs
git remote show origin           # Detailed remote info

# Add remote
git remote add origin https://github.com/user/repo.git
git remote add upstream https://github.com/original/repo.git

# Remove remote
git remote remove origin
git remote rm origin             # Alias for remove

# Rename remote
git remote rename origin old-origin

# Change remote URL
git remote set-url origin https://new-url.git
git remote set-url --add origin https://additional-url.git

# Prune remote branches
git remote prune origin          # Remove stale remote-tracking branches
git remote prune --dry-run origin

# Repack repository
git repack
git repack -a                    # Include all objects
git repack -d                    # Remove redundant packs

# Aggressive repack
git repack -a -d --depth=250 --window=250

# Repack with progress
git repack -a -d --progress

# Replace object with another
git replace bad-commit good-commit

# List replacements
git replace -l
git replace --list

# Delete replacement
git replace -d bad-commit

# Enable rerere
git config rerere.enabled true

# Status of rerere
git rerere status
git rerere diff

# Clear rerere database
git rerere clear
git rerere forget file.txt      # Forget resolution for file

# Reset modes
git reset --soft HEAD~1          # Keep changes staged
git reset --mixed HEAD~1         # Keep changes unstaged (default)
git reset --hard HEAD~1          # Discard all changes

# Reset to specific commit
git reset --hard abc1234
git reset --soft v1.0

# Reset specific files
git reset HEAD file.txt          # Unstage file
git reset file.txt               # Same as above

# Reset with paths
git reset HEAD~1 -- file.txt     # Reset file to previous version

# Interactive reset
git reset -p                     # Interactively unstage hunks

# Restore working directory (Git 2.23+)
git restore file.txt             # Discard changes
git restore .                    # Restore all files

# Restore from specific commit
git restore --source=HEAD~1 file.txt
git restore --source=main file.txt

# Restore staged files
git restore --staged file.txt    # Unstage file
git restore --staged .           # Unstage all files

# Restore both working directory and staged
git restore --staged --worktree file.txt

# Interactive restore
git restore -p file.txt          # Interactive hunks

# List commits
git rev-list HEAD                # All reachable commits from HEAD
git rev-list HEAD~5..HEAD        # Range of commits
git rev-list --count HEAD        # Count commits

# With objects
git rev-list --objects HEAD      # Include trees and blobs
git rev-list --objects --all     # All reachable objects

# Filtering
git rev-list --since="1 week ago" HEAD
git rev-list --author="John Doe" HEAD
git rev-list --grep="bug" HEAD

# Advanced options
git rev-list --pretty HEAD       # Pretty format
git rev-list --reverse HEAD      # Reverse chronological order
git rev-list --ancestry-path main..feature

# Parse revisions
git rev-parse HEAD               # Full SHA-1 of HEAD
git rev-parse --short HEAD       # Abbreviated SHA-1
git rev-parse main               # Full SHA-1 of main

# Repository paths
git rev-parse --git-dir          # .git directory path
git rev-parse --show-toplevel    # Repository root
git rev-parse --show-prefix      # Current directory relative to root

# Branch information
git rev-parse --abbrev-ref HEAD  # Current branch name
git rev-parse --symbolic-full-name HEAD

# Verify objects
git rev-parse --verify HEAD     # Verify and return SHA-1
git rev-parse --verify HEAD^{commit}  # Verify it's a commit

# Revert single commit
git revert HEAD                  # Revert last commit
git revert abc1234               # Revert specific commit

# Revert multiple commits
git revert HEAD~3..HEAD          # Revert range
git revert --no-commit HEAD~3..HEAD  # Don't auto-commit

# Revert merge commit
git revert -m 1 merge-commit     # Revert to first parent
git revert -m 2 merge-commit     # Revert to second parent

# Continue/abort revert
git revert --continue            # After resolving conflicts
git revert --abort               # Abort revert operation

# Revert with custom message
git revert -e HEAD               # Edit commit message
git revert --no-edit HEAD        # Use default message