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Update SessionStart hook command to handle CLAUDE_PLUGIN_ROOT template substitution path across Linux, Windows with WSL bash.exe and Windows with Git Bash #421

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Update SessionStart hook command to handle CLAUDE_PLUGIN_ROOT template substitution path across Linux, Windows with WSL bash.exe and Windows with Git Bash #421

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4e8474c
Update command to handle CLAUDE_PLUGIN_ROOT path
pedropaulovc Feb 5, 2026
534e5bb
Merge branch 'main' into hooks-polyglot
pedropaulovc Feb 5, 2026
15b2c4a
Fix command formatting in hooks.json
pedropaulovc Feb 5, 2026
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25 changes: 24 additions & 1 deletion hooks/hooks.json
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Original file line number Diff line number Diff line change
Expand Up @@ -5,8 +5,31 @@
"matcher": "startup|resume|clear|compact",
"hooks": [
{
"_comment": [
"Claude Code injects it via template substitution BEFORE the shell runs,",
"so ${CLAUDE_PLUGIN_ROOT} expands but bash never sees the actual env var.",
"This means bash parameter operations (${#VAR}, ${VAR//p/r}) on it directly return empty.",
"On Windows, CLAUDE_PLUGIN_ROOT is a Windows path (e.g. C:\\Users\\myuser\\.claude\\plugins\\...)",
"which conflicts with Bash's string escaping.",
"Fix: assign the template-expanded value to a local bash",
"variable (RAW) first, then operate on RAW.",
"",
"This command must work across three bash environments:",
" 1. Git Bash on Windows: OSTYPE=msys, OS=Windows_NT, paths like /c/Users/...",
" 2. WSL bash: OSTYPE=linux-gnu, OS unset, paths like /mnt/c/Users/...",
" 3. Native Linux /bin/bash: OSTYPE=linux-gnu, no drive letter conversion needed",
"",
"Path resolution steps:",
" 1. Capture CLAUDE_PLUGIN_ROOT into RAW (makes it a real bash variable)",
" 2. Replace backslashes with forward slashes: C:\\Users\\... -> C:/Users/...",
" 3. Extract drive letter (C) and rest of path (/Users/...)",
" 4. If no colon found (native Linux), use RAW as-is",
" 5. If OS=Windows_NT (Git Bash): prefix with / -> /c/Users/...",
" 6. Otherwise (WSL): prefix with /mnt/ -> /mnt/c/Users/..."
],
"_debug_echo": "echo >&2; echo \"[hook-debug] RAW=[$RAW]\" >&2; echo \"[hook-debug] UNIX_PATH=[$PLUGIN_UNIX_PATH]\" >&2; echo \"[hook-debug] DRIVE=[$DRIVE] REST=[$REST] OS=[$OS] RESOLVED=[$RESOLVED]\" >&2; echo >&2;",
"type": "command",
"command": "${CLAUDE_PLUGIN_ROOT}/hooks/session-start.sh",
"command": "bash -c 'RAW=\"${CLAUDE_PLUGIN_ROOT}\"; PLUGIN_UNIX_PATH=\"${RAW//\\\\\/\/}\"; DRIVE=\"${PLUGIN_UNIX_PATH%%:*}\"; REST=\"${PLUGIN_UNIX_PATH#*:}\"; if [ \"$DRIVE\" = \"$PLUGIN_UNIX_PATH\" ]; then RESOLVED=\"$PLUGIN_UNIX_PATH\"; elif [ \"$OS\" = \"Windows_NT\" ]; then RESOLVED=\"\/${DRIVE,,}$REST\"; else RESOLVED=\"\/mnt\/${DRIVE,,}$REST\"; fi; \"$RESOLVED\/hooks\/session-start.sh\"'",
"async": true
}
]
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