scripts/setup.sh and scripts/setup-windows.ps1 carried their own copy of
the release download: resolve the latest tag, fetch the archive, unpack it
into the install directory. Two implementations of the same step drifted
apart: the setup scripts did not follow the installers as those gained
their checks, their architecture selection and their staging directory.
Both setup scripts now fetch the installer from the origin and branch they
are themselves served from and hand the download and install over to it,
so there is exactly one implementation and the setup scripts behave like
the installers: the same conditions stop them with a non-zero exit before
anything is installed, setup-windows.ps1 selects the archive through the
installer's architecture detection instead of always amd64 (CBM_ARCH pins
it) and stages in a freshly created directory, and the file is pure ASCII
again. CBM_DOWNLOAD_URL, the
installers' download-base override, also moves the installer fetch so both
scripts can be driven against a local fixture.
Everything the setup scripts do beyond installing the binary is unchanged:
the --from-source / -FromSource builds, the interactive Claude Code
configuration, the PATH hint, the git-hook activation and the uninstall
notes.
tests/test_setup_scripts_contract.sh runs setup.sh against a loopback
fixture release built from a stub binary, in file mode and in curl | bash
mode, covers the cases in which the installer refuses, and pins the static
contract for setup-windows.ps1. It is Step 0z of scripts/test.sh.
Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>
