From 67fcd5c476797f597dab6cb05163abbf1a5211ff Mon Sep 17 00:00:00 2001
From: suna <sunasrd@gmail.com>
Date: Tue, 4 Aug 2026 11:15:18 +0200
Subject: [PATCH] fix: check for git before verifying the installation

The installers run `codeplain --status` to verify the setup, but the CLI
imports GitPython, which fails at import time when the git executable is
missing. Users without git saw a raw Python traceback ending in
GitNotInstalledError, followed by advice to restart the terminal or
reinstall -- neither of which fixes a missing git.

Check for git alongside the existing uv check, before any prompts or
package installs, and exit with the platform's install URL. Verify that
git actually runs rather than trusting a resolvable name, since a stale
shim can satisfy the lookup without a working git behind it.

This complements the CLI-side GitNotInstalledError already on main: the
installer now stops before that error can surface, and the friendly CLI
error remains the fallback for anyone who bypasses the installer.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
---
 install/bash/install.sh        | 41 ++++++++++++++++++++++++++++++++
 install/powershell/install.ps1 | 43 ++++++++++++++++++++++++++++++++++
 2 files changed, 84 insertions(+)

diff --git a/install/bash/install.sh b/install/bash/install.sh
index 72b55a93..dfd371e2 100755
--- a/install/bash/install.sh
+++ b/install/bash/install.sh
@@ -42,6 +42,38 @@ install_uv() {
     export PATH="$HOME/.local/bin:$PATH"
 }
 
+# A stale shim can make git resolvable without a working git behind it, so
+# verify git actually runs rather than trusting command -v alone.
+git_available() {
+    command -v git &> /dev/null && git --version &> /dev/null
+}
+
+# Print install instructions for the current platform and exit. codeplain uses
+# git to checkpoint the code it renders, and GitPython fails at import time
+# when the git executable is missing, so 'codeplain --status' would die with a
+# raw traceback that says nothing about the actual cause.
+require_git() {
+    echo -e "  ${YELLOW}${BOLD}Git is required to continue, but it doesn't appear to be installed.${NC}"
+    echo ""
+    echo -e "  Please install Git by following the instructions on the official Git website:"
+    echo ""
+    case "$OSTYPE" in
+        darwin*)
+            echo -e "  ${WHITE}${BOLD}https://git-scm.com/install/mac${NC}"
+            ;;
+        msys* | cygwin* | win32*)
+            echo -e "  ${WHITE}${BOLD}https://git-scm.com/install/win${NC}"
+            ;;
+        *)
+            echo -e "  ${WHITE}${BOLD}https://git-scm.com/install/linux${NC}"
+            ;;
+    esac
+    echo ""
+    echo -e "  ${GRAY}Once Git is installed, restart your terminal and run this installer again.${NC}"
+    echo ""
+    exit 1
+}
+
 # Trim leading/trailing whitespace (spaces, tabs, newlines, carriage returns).
 # Users often copy the API key with surrounding whitespace or newlines.
 trim_whitespace() {
@@ -77,6 +109,15 @@ fi
 echo -e "${GREEN}✓${NC} uv detected"
 echo -e ""
 
+# Checked here, alongside uv, so a missing prerequisite stops the installer
+# before the user answers any prompts rather than at the --status check below.
+if ! git_available; then
+    require_git
+fi
+
+echo -e "${GREEN}✓${NC} git detected"
+echo -e ""
+
 # Install or upgrade codeplain using uv tool
 if uv tool list 2>/dev/null | grep -q "^codeplain"; then
     CURRENT_VERSION=$(uv tool list 2>/dev/null | grep "^codeplain" | sed 's/codeplain v//')
diff --git a/install/powershell/install.ps1 b/install/powershell/install.ps1
index 0ac18e80..a466cc59 100644
--- a/install/powershell/install.ps1
+++ b/install/powershell/install.ps1
@@ -61,6 +61,40 @@ function Install-Uv {
     }
 }
 
+# A stale shim can make git resolvable without a working git behind it, so
+# verify git actually runs rather than trusting Get-Command alone.
+function Test-GitAvailable {
+    if (-not (Get-Command git -ErrorAction SilentlyContinue)) { return $false }
+    try {
+        & git --version *> $null
+        return ($LASTEXITCODE -eq 0)
+    } catch {
+        return $false
+    }
+}
+
+# Print install instructions for the current platform and exit. codeplain uses
+# git to checkpoint the code it renders, and GitPython fails at import time
+# when the git executable is missing, so 'codeplain --status' would die with a
+# raw traceback that says nothing about the actual cause.
+function Assert-Git {
+    Write-Host "  ${YELLOW}${BOLD}Git is required to continue, but it doesn't appear to be installed.${NC}"
+    Write-Host ""
+    Write-Host "  Please install Git by following the instructions on the official Git website:"
+    Write-Host ""
+    if ($IsWindows -or ($env:OS -eq "Windows_NT")) {
+        Write-Host "  ${WHITE}${BOLD}https://git-scm.com/install/win${NC}"
+    } elseif ($IsMacOS) {
+        Write-Host "  ${WHITE}${BOLD}https://git-scm.com/install/mac${NC}"
+    } else {
+        Write-Host "  ${WHITE}${BOLD}https://git-scm.com/install/linux${NC}"
+    }
+    Write-Host ""
+    Write-Host "  ${GRAY}Once Git is installed, restart your terminal and run this installer again.${NC}"
+    Write-Host ""
+    exit 1
+}
+
 # Verify an API key against the Codeplain API's /status endpoint.
 # Returns a status string: "valid" (HTTP 200), "invalid" (HTTP 401), or
 # "error" (could not reach the API). This checks only the API key.
@@ -99,6 +133,15 @@ if (-not (Get-Command uv -ErrorAction SilentlyContinue)) {
 Write-Host "${GREEN}✓${NC} uv detected"
 Write-Host ""
 
+# Checked here, alongside uv, so a missing prerequisite stops the installer
+# before the user answers any prompts rather than at the --status check below.
+if (-not (Test-GitAvailable)) {
+    Assert-Git
+}
+
+Write-Host "${GREEN}✓${NC} git detected"
+Write-Host ""
+
 try {
     $uvOutput = uv tool list 2>$null
 } catch {