Modified the isisVarInit.py script (#3945)

* Removed version number from filename.

* feat: Changed the name of the VarInit script, changed how it worked
internally, and made it write out isis-activate.* and isis_deactivate.*
files.

* Fix: Now has correct csh syntax, updated mkdir() with a proper docstring
and to return a string (only main should print(), functions shouldn't or
should log, but that's overkill for this).

README.md

@@ -92,15 +92,15 @@ This installation guide is for ISIS users interested in installing ISIS (3.6.0)+
         #Execute the ISIS variable initialization script with default arguments.
         #This script prepares default values for:  $ISISROOT, $ISISDATA, $ISISTESTDATA
 
-        python $CONDA_PREFIX/scripts/isis3VarInit.py
+        python $CONDA_PREFIX/scripts/isisVarInit.py
 
 
     Executing this script with no arguments will result in $ISISDATA=$CONDA\_PREFIX/data, and $ISISTESTDATA=$CONDA\_PREFIX/testdata. The user can specify different directories for both of these optional values:
 
-        python $CONDA_PREFIX/scripts/isis3VarInit.py --data-dir=[path to data directory]  --test-dir=[path to test data directory]
+        python $CONDA_PREFIX/scripts/isisVarInit.py --data-dir=[path to data directory]  --test-dir=[path to test data directory]
 
 
-    More information about the ISISDATA environment variable and the ISIS Data Area can be found [here]("#The-ISIS-Data-Area"). Now everytime the isis environment is activated, $ISISROOT, $ISISDATA, and $ISISTESTDATA will be set to the values passed to isis3VarInit.py. This does not happen retroactively, re-activate the isis envionment with one of the following commands:
+    More information about the ISISDATA environment variable and the ISIS Data Area can be found [here]("#The-ISIS-Data-Area"). Now everytime the isis environment is activated, $ISISROOT, $ISISDATA, and $ISISTESTDATA will be set to the values passed to isisVarInit.py. This does not happen retroactively, so re-activate the isis envionment with one of the following commands:
 
         for Anaconda 3.4 and up - conda activate isis
         prior to Anaconda 3.4 - source activate isis

isis/scripts/isisVarInit.py

@@ -0,0 +1,146 @@
+#!/usr/bin/env python
+"""
+This program builds shell scripts that define the ISIS environment
+variables that are sourced during conda environment activation and
+removed at deactivation.
+
+If the directories don't exist, they are created.  If their path is
+not specified, they are placed in $ISISROOT.
+"""
+
+import argparse
+import os
+from pathlib import Path
+
+# This is free and unencumbered software released into the public domain.
+#
+# The authors of ISIS do not claim copyright on the contents of this file.
+# For more details about the LICENSE terms and the AUTHORS, you will
+# find files of those names at the top level of this repository.
+#
+# SPDX-License-Identifier: CC0-1.0
+
+
+def mkdir(p: Path) -> str:
+    """Returns a string with a message about the creation or existance
+    of the path, *p*."""
+    if p.exists():
+        return f"{p} exists, don't need to create."
+    else:
+        p.mkdir(parents=False)
+        return f"Created {p}"
+
+
+def activate_text(shell: dict, env_vars: dict) -> str:
+    """Returns the formatted text to write to the activation script
+    based on the passed dictionaries."""
+
+    lines = [shell["shebang"]]
+    for k, v in env_vars.items():
+        lines.append(shell["activate"].format(k, v))
+
+    if shell["activate_extra"] != "":
+        lines.append(shell["activate_extra"])
+
+    lines.append("cat $ISISROOT/version")
+
+    return "\n".join(lines)
+
+
+def deactivate_text(shell: dict, env_vars: dict) -> str:
+    """Returns the formatted text to write to the deactivation script
+    based on the passed dictionaries."""
+
+    lines = [shell["shebang"]]
+    for k in env_vars.keys():
+        lines.append(shell["deactivate"].format(k))
+
+    return "\n".join(lines)
+
+
+# Set up and then parse the command line:
+parser = argparse.ArgumentParser(description=__doc__)
+
+parser.add_argument(
+    "-d",
+    "--data-dir",
+    default=os.environ["CONDA_PREFIX"] + "/data",
+    type=Path,
+    help="ISIS Data Directory, default: %(default)s",
+)
+parser.add_argument(
+    "-t",
+    "--test-dir",
+    default=os.environ["CONDA_PREFIX"] + "/testData",
+    type=Path,
+    help="ISIS Test Data Directory, default: %(default)s",
+)
+
+parser.add_argument(
+    "-a",
+    "--ale-dir",
+    default=os.environ["CONDA_PREFIX"] + "/aleData",
+    type=Path,
+    help="ISIS Ale Data Directory, default: %(default)s",
+)
+args = parser.parse_args()
+
+print("-- ISIS Data Directories --")
+# Create the data directories:
+print(mkdir(args.data_dir))
+print(mkdir(args.test_dir))
+print(mkdir(args.ale_dir))
+
+print("-- Conda activation and deactivation scripts --")
+# Create the conda activation and deactivation directories:
+activate_dir = Path(os.environ["CONDA_PREFIX"]) / "etc/conda/activate.d"
+deactivate_dir = Path(os.environ["CONDA_PREFIX"]) / "etc/conda/deactivate.d"
+
+print(mkdir(activate_dir))
+print(mkdir(deactivate_dir))
+
+# Set the environment variables to manage
+env_vars = dict(
+    ISISROOT=os.environ["CONDA_PREFIX"],
+    ISISDATA=args.data_dir,
+    ISISTESTDATA=args.test_dir,
+    ALESPICEROOT=args.ale_dir
+)
+
+# These dicts define the unique aspects of the shell languages
+# for setting and unsetting the environment variables.
+
+sh = dict(  # this covers bash and zsh
+    extension=".sh",
+    shebang="#!/usr/bin/env sh",
+    activate="export {}={}",
+    activate_extra="",
+    deactivate="unset {}"
+)
+
+csh = dict(
+    extension=".csh",
+    shebang="#!/usr/bin/env csh",
+    activate="setenv {} {}",
+    activate_extra="source $CONDA_PREFIX/scripts/tabCompletion.csh",
+    deactivate="unsetenv {}"
+)
+
+fish = dict(
+    extension=".fish",
+    shebang="#!/usr/bin/env fish",
+    activate="set -gx {} {}",
+    activate_extra="",
+    deactivate="set -e {}"
+)
+
+# Loop over the shell types and create the correct scripts associated with
+# each:
+for shell in (sh, csh, fish):
+    a_path = activate_dir / ("isis-activate" + shell["extension"])
+    a_path.write_text(activate_text(shell, env_vars))
+    print(f"Wrote {a_path}")
+
+    d_path = deactivate_dir / ("isis-deactivate" + shell["extension"])
+    d_path.write_text(deactivate_text(shell, env_vars))
+    print(f"Wrote {d_path}")