render() env emission doesn't escape or block-scalar multiline values

[vsilent]

Location

src/cli/generator/compose.rs:602 — the render() function's env emission loop.

Problem

The env renderer uses a naive format string:

format!("      {}: \"{}\"\n", key, value)

This has three bugs:

1. Multiline values are folded into a single line

YAML double-quoted scalars fold newlines into spaces. A multiline env value like:

GITLAB_OMNIBUS_CONFIG: |
  external_url 'http://git.example.com'
  nginx['listen_port'] = 80

arrives at docker compose config as:

external_url 'http://git.example.com' nginx['listen_port'] = 80 ...

which is a Ruby syntax error — gitlab-ctl reconfigure never applies it.

2. Unescaped " in values

Values containing literal double quotes break the YAML scalar quoting.

3. yaml_quote already exists and is not used

yaml_quote at line 561 handles escaping but is not called on the env emission path.

Fix

Use a YAML block scalar (|) for values containing newlines, and call yaml_quote for simple values. The change is in the env emission loop in render().

Impact

Every stack with a multiline env value. Confirmed with the GitLab CE stack (GITLAB_OMNIBUS_CONFIG).

Separate issues (do not bundle)

• shm_size silently dropped from generated compose
• Double-wrapped CMD-SHELL in healthcheck (CMD-SHELL CMD-SHELL ...)