Unexpected behavior of runtime.txt configuration file

[LuisGMM]

Bug description

According to the guide (https://mybinder.readthedocs.io/en/latest/howto/languages.html#specifying-a-version-of-python) when using the requirements.txt file, a second file called runtime.txt can be used to specify the python version, but it does not seem to work (completely?). In the log below can be seen as it apparently loads an environment with python 3.10:

Building conda environment for python=3.10Using PythonBuildPack builder
Building conda environment for python=3.10Building conda environment for python=3.10

But a few lines after, it starts asking the modules for other version of python

Log

``` Waiting for build to start... Picked Git content provider. Cloning into '/tmp/repo2docker9hl7vaq0'... HEAD is now at 67d89f45 Removed requirements.txt and runtime.txt Building conda environment for python=3.10Using PythonBuildPack builder Building conda environment for python=3.10Building conda environment for python=3.10Step 1/53 : FROM buildpack-deps:bionic ``` ``` ---> 2db1fa0a8732 Step 2/53 : ENV DEBIAN_FRONTEND=noninteractive ---> Using cache ---> c4be527842e7 Step 3/53 : RUN apt-get -qq update && apt-get -qq install --yes --no-install-recommends locales > /dev/null && apt-get -qq purge && apt-get -qq clean && rm -rf /var/lib/apt/lists/* ---> Using cache ---> 522790fe583d Step 4/53 : RUN echo "en_US.UTF-8 UTF-8" > /etc/locale.gen && locale-gen ---> Using cache ---> 0a1b0e069082 Step 5/53 : ENV LC_ALL en_US.UTF-8 ---> Using cache ---> 8e66f6653989 Step 6/53 : ENV LANG en_US.UTF-8 ---> Using cache ---> 22edaf4e8453 Step 7/53 : ENV LANGUAGE en_US.UTF-8 ---> Using cache ---> 36af3a79fe10 Step 8/53 : ENV SHELL /bin/bash ---> Using cache ---> e09e0d6bab8f Step 9/53 : ARG NB_USER ---> Using cache ---> 8bfc8147f921 Step 10/53 : ARG NB_UID ---> Using cache ---> 0f412242aeed Step 11/53 : ENV USER ${NB_USER} ---> Using cache ---> 6d30f4e83977 Step 12/53 : ENV HOME /home/${NB_USER} ---> Using cache ---> 3e7464d59708 Step 13/53 : RUN groupadd --gid ${NB_UID} ${NB_USER} && useradd --comment "Default user" --create-home --gid ${NB_UID} --no-log-init --shell /bin/bash --uid ${NB_UID} ${NB_USER} ---> Using cache ---> 8664e4fba62d Step 14/53 : RUN apt-get -qq update && apt-get -qq install --yes --no-install-recommends less unzip > /dev/null && apt-get -qq purge && apt-get -qq clean && rm -rf /var/lib/apt/lists/* ---> Using cache ---> 24426d7ac731 Step 15/53 : EXPOSE 8888 ---> Using cache ---> b74cd1477a99 Step 16/53 : ENV APP_BASE /srv ---> Using cache ---> 44415ebdd4c7 Step 17/53 : ENV CONDA_DIR ${APP_BASE}/conda ---> Using cache ---> ce293998e209 Step 18/53 : ENV NB_PYTHON_PREFIX ${CONDA_DIR}/envs/notebook ---> Using cache ---> 304392d6afcf Step 19/53 : ENV NPM_DIR ${APP_BASE}/npm ---> Using cache ---> 592af4ed4ec6 Step 20/53 : ENV NPM_CONFIG_GLOBALCONFIG ${NPM_DIR}/npmrc ---> Using cache ---> 4eba97d79554 Step 21/53 : ENV NB_ENVIRONMENT_FILE /tmp/env/environment.lock ---> Using cache ---> 5b0fe08efc5e Step 22/53 : ENV MAMBA_ROOT_PREFIX ${CONDA_DIR} ---> Using cache ---> 1e5f22ad77a4 Step 23/53 : ENV MAMBA_EXE ${CONDA_DIR}/bin/mamba ---> Using cache ---> 2778a0246188 Step 24/53 : ENV KERNEL_PYTHON_PREFIX ${NB_PYTHON_PREFIX} ---> Using cache ---> e7362f318a58 Step 25/53 : ENV PATH ${NB_PYTHON_PREFIX}/bin:${CONDA_DIR}/bin:${NPM_DIR}/bin:${PATH} ---> Using cache ---> 2b15b72f0c01 Step 26/53 : COPY --chown=1000:1000 build_script_files/-2fusr-2flib-2fpython3-2e8-2fsite-2dpackages-2frepo2docker-2fbuildpacks-2fconda-2factivate-2dconda-2esh-391af5 /etc/profile.d/activate-conda.sh ---> Using cache ---> eb2154f05724 Step 27/53 : COPY --chown=1000:1000 build_script_files/-2fusr-2flib-2fpython3-2e8-2fsite-2dpackages-2frepo2docker-2fbuildpacks-2fconda-2fenvironment-2elock-1dbdca /tmp/env/environment.lock ---> Using cache ---> f6cf8879c6a9 Step 28/53 : COPY --chown=1000:1000 build_script_files/-2fusr-2flib-2fpython3-2e8-2fsite-2dpackages-2frepo2docker-2fbuildpacks-2fconda-2finstall-2dbase-2denv-2ebash-8fbb20 /tmp/install-base-env.bash ---> Using cache ---> 70317889a609 Step 29/53 : RUN TIMEFORMAT='time: %3R' bash -c 'time /tmp/install-base-env.bash' && rm -rf /tmp/install-base-env.bash /tmp/env ---> Using cache ---> 5ab596de5d78 Step 30/53 : RUN mkdir -p ${NPM_DIR} && chown -R ${NB_USER}:${NB_USER} ${NPM_DIR} ---> Using cache ---> 2412b0a3c5da Step 31/53 : USER root ---> Using cache ---> e254b2ebaad0 Step 32/53 : ARG REPO_DIR=${HOME} ---> Using cache ---> 39a05327ef23 Step 33/53 : ENV REPO_DIR ${REPO_DIR} ---> Using cache ---> e0307458f8be Step 34/53 : WORKDIR ${REPO_DIR} ---> Using cache ---> f95447dfd3e5 Step 35/53 : RUN chown ${NB_USER}:${NB_USER} ${REPO_DIR} ---> Using cache ---> 3b1f38eaf32f Step 36/53 : ENV PATH ${HOME}/.local/bin:${REPO_DIR}/.local/bin:${PATH} ---> Using cache ---> 4b6fde76ebe8 Step 37/53 : ENV CONDA_DEFAULT_ENV ${KERNEL_PYTHON_PREFIX} ---> Using cache ---> cd87cab70e19 Step 38/53 : COPY --chown=1000:1000 src/binder/requirements.txt ${REPO_DIR}/binder/requirements.txt ---> Using cache ---> 5dcb69e560cf Step 39/53 : USER ${NB_USER} ---> Using cache ---> 22daa31b5c0b Step 40/53 : RUN ${KERNEL_PYTHON_PREFIX}/bin/pip install --no-cache-dir -r "binder/requirements.txt" ---> Running in 74264c6a62f3 Collecting poliastro Cloning https://github.com/poliastro/poliastro.git to /tmp/pip-install-iw4ztkjq/poliastro_70ce0be933f04146abae2a896501d8bd  Running command git clone --filter=blob:none -q https://github.com/poliastro/poliastro.git /tmp/pip-install-iw4ztkjq/poliastro_70ce0be933f04146abae2a896501d8bd  Resolved https://github.com/poliastro/poliastro.git to commit da11159b8d00e56125ecff741d683dd06dcd8be8 Installing build dependencies: started Installing build dependencies: finished with status 'done' Getting requirements to build wheel: started Getting requirements to build wheel: finished with status 'done' Preparing metadata (pyproject.toml): started Preparing metadata (pyproject.toml): finished with status 'done' Collecting jupytext>=1.13.3 Downloading jupytext-1.13.6-py3-none-any.whl (297 kB) ERROR: Could not find a version that satisfies the requirement astropy<6,>=5.0 (from poliastro) (from versions: 0.1, 0.2, 0.2.1, 0.2.2, 0.2.3, 0.2.4, 0.2.5, 0.3, 0.3.1, 0.3.2, 0.4rc1, 0.4rc2, 0.4, 0.4.1, 0.4.2, 0.4.3, 0.4.4, 0.4.5, 0.4.6, 1.0rc1, 1.0rc2, 1.0, 1.0.1, 1.0.2, 1.0.3, 1.0.4, 1.0.5, 1.0.6, 1.0.7, 1.0.8, 1.0.9, 1.0.10, 1.0.11, 1.0.12, 1.0.13, 1.1b1, 1.1rc1, 1.1rc2, 1.1, 1.1.post1, 1.1.post2, 1.1.1, 1.1.2, 1.2rc1, 1.2, 1.2.1, 1.2.2, 1.3rc1, 1.3, 1.3.1, 1.3.2, 1.3.3, 2.0rc1, 2.0, 2.0.1, 2.0.2, 2.0.3, 2.0.4, 2.0.5, 2.0.6, 2.0.7, 2.0.8, 2.0.9, 2.0.10, 2.0.11, 2.0.12, 2.0.13, 2.0.14, 2.0.15, 2.0.16, 3.0rc1, 3.0rc2, 3.0, 3.0.1, 3.0.2, 3.0.3, 3.0.4, 3.0.5, 3.1rc1, 3.1rc2, 3.1, 3.1.1, 3.1.2, 3.2rc1, 3.2rc2, 3.2, 3.2.1, 3.2.2, 3.2.3, 4.0rc1, 4.0rc2, 4.0, 4.0.1, 4.0.1.post1, 4.0.2, 4.0.3, 4.0.4, 4.0.5, 4.0.6.dev27461, 4.0.6, 4.1rc1, 4.1rc2, 4.1, 4.2rc1, 4.2, 4.2.1, 4.3rc1, 4.3, 4.3.post1, 4.3.1) ERROR: No matching distribution found for astropy<6,>=5.0 Removing intermediate container 74264c6a62f3 The command '/bin/sh -c ${KERNEL_PYTHON_PREFIX}/bin/pip install --no-cache-dir -r "binder/requirements.txt"' returned a non-zero code: 1Built image, launching... Failed to connect to event stream ```

our requirements.txt file is

git+https://github.com/poliastro/poliastro.git#egg=poliastro

jupytext>=1.13.3  

and the runtime.txt is

python-3.10

They are both located in a folder a the root of the project -> src/binder/

It is worth mentioning that trying the configuration file environment.yml containing

name: python 3.10
dependencies:
  - python=3.10
  - jupytext>=1.13.3

placed in the same folder works fine.

Also, may it be related to issue 252?

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[astrojuanlu]

This just happened to me again in a different repository, any comment on what might be happening here?

[astrojuanlu]

Wondering if this should really belong to https://github.com/jupyterhub/repo2docker/