Pre-Commit Hooks

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Overview

• Lint and syntax checks
• Code formatting enforcement
• Preventing commits of large or forbidden files
• Custom project-specific validation

• Before a commit, Diversion runs the .dvhooks/pre-commit script with the committed files as command-line arguments
• Exit code 0 means the hook passed - the commit proceeds
• Any non-zero exit code means the hook failed - the commit is blocked
• The hook’s stdout/stderr output is displayed to the user

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Creating a Pre-Commit Hook

mkdir .dvhooks

#!/bin/sh
echo "Running pre-commit checks..."

# Committed files are passed as arguments ($@)
for file in "$@"; do
  if echo "$file" | grep -q '\.js$'; then
    if grep -q "console.log" "$file"; then
      echo "Error: Remove console.log from $file before committing."
      exit 1
    fi
  fi
done

echo "All checks passed."
exit 0

@echo off
echo Running pre-commit checks...

REM Committed files are passed as arguments (%*)
for %%f in (%*) do (
  echo Checking %%f
)

echo All checks passed.
exit /b 0

Write-Host "Running pre-commit checks..."

# Committed files are passed as arguments ($args)
foreach ($file in $args) {
  if ($file -match '\.js$') {
    if (Select-String -Path $file -Pattern "console.log" -Quiet) {
      Write-Host "Error: Remove console.log from $file before committing."
      exit 1
    }
  }
}

Write-Host "All checks passed."
exit 0

chmod +x .dvhooks/pre-commit

dv commit .dvhooks -m "Add pre-commit hook"

​

File Arguments

#!/bin/sh
# Reject files larger than 100MB
MAX_SIZE=$((100 * 1024 * 1024))
for file in "$@"; do
  if [ -f "$file" ]; then
    size=$(stat -f%z "$file" 2>/dev/null || stat -c%s "$file" 2>/dev/null)
    if [ "$size" -gt "$MAX_SIZE" ]; then
      echo "Error: $file is too large ($(($size / 1024 / 1024))MB, limit 100MB)."
      exit 1
    fi
  fi
done

exit 0

@echo off
REM Check committed files
for %%f in (%*) do (
  echo Checking: %%f
)
exit /b 0

​

Environment Variables

#!/bin/sh
# Require commit messages to contain a ticket reference (e.g., PROJ-123)
if ! echo "$DV_COMMIT_MESSAGE" | grep -qE '[A-Z]+-[0-9]+'; then
  echo "Error: Commit message must include a ticket number (e.g., PROJ-123)."
  echo "Your message: $DV_COMMIT_MESSAGE"
  exit 1
fi

exit 0

@echo off
REM Require commit messages to contain a ticket reference (e.g., PROJ-123)
echo %DV_COMMIT_MESSAGE% | findstr /R "[A-Z]*-[0-9]*" >nul 2>&1
if %errorlevel% neq 0 (
  echo Error: Commit message must include a ticket number (e.g., PROJ-123).
  echo Your message: %DV_COMMIT_MESSAGE%
  exit /b 1
)

exit /b 0

​

Skipping Hooks

dv commit -a -m "quick fix" --no-verify

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Behavior Details

• Timeout: Hooks have a 60-second timeout. If the hook doesn’t finish in time, the commit is blocked with a timeout message.
• Working directory: The hook runs with the workspace root as its working directory.
• Output limit: Hook output is capped at 1 MB. Output beyond that limit is truncated.
• Output display: Hook output is always shown to the user, whether the hook passes or fails.
• Platform detection:
  • Mac/Linux: Diversion looks for an executable file named pre-commit in .dvhooks/. If the file exists but isn’t executable, you’ll see an error prompting you to run chmod +x.
  • Windows: Diversion looks for pre-commit.bat, pre-commit.cmd, or pre-commit.ps1 in .dvhooks/ (checked in that order).