[SCons] Change prefix default if conda is detected

.github/workflows/main.yml

@@ -313,9 +313,8 @@ jobs:
           cython boost-cpp fmt eigen yaml-cpp h5py pandas libgomp openblas pytest
       - name: Build Cantera
         run: |
-          scons build extra_inc_dirs=$CONDA_PREFIX/include:$CONDA_PREFIX/include/eigen3 \
-          extra_lib_dirs=$CONDA_PREFIX/lib system_fmt=y system_eigen=y system_yamlcpp=y \
-          system_sundials=y blas_lapack_libs='lapack,blas' -j2 VERBOSE=True debug=n \
+          scons build system_fmt=y system_eigen=y system_yamlcpp=y system_sundials=y \
+          blas_lapack_libs='lapack,blas' -j2 VERBOSE=True debug=n \
           optimize_flags='-O3 -ffast-math -fno-finite-math-only'
       - name: Test Cantera
         run: scons test show_long_tests=yes verbose_tests=yes

SConstruct

@@ -217,8 +217,12 @@ config_options = [
         }),
     PathOption(
         "prefix",
-        """Set this to the directory where Cantera should be installed. On Windows
-           systems, '$ProgramFiles' typically refers to "C:\Program Files".""",
+        """Set this to the directory where Cantera should be installed. If the Python
+           executable found during compilation is managed by 'conda', the installation
+           'prefix' defaults to the corresponding environment and the 'conda' layout
+           will be used for installation (specifying any of the options 'prefix',
+           'python_prefix', 'python_cmd' or 'layout' will override this default). On
+           Windows systems, '$ProgramFiles' typically refers to "C:\Program Files".""",
         {"Windows": "$ProgramFiles\Cantera", "default": "/usr/local"},
         PathVariable.PathAccept),
     PathOption(
@@ -483,12 +487,16 @@ config_options = [
     Option(
         "extra_inc_dirs",
         """Additional directories to search for header files, with multiple
-           directories separated by colons (*nix, macOS) or semicolons (Windows)""",
+           directories separated by colons (*nix, macOS) or semicolons (Windows).
+           If an active 'conda' environment is detected, the corresponding include
+           path is automatically added.""",
         ""),
     Option(
         "extra_lib_dirs",
         """Additional directories to search for libraries, with multiple
-           directories separated by colons (*nix, macOS) or semicolons (Windows)""",
+           directories separated by colons (*nix, macOS) or semicolons (Windows).
+           If an active 'conda' environment is detected, the corresponding library
+           path is automatically added.""",
         ""),
     PathOption(
         "boost_inc_dir",
@@ -550,12 +558,17 @@ config_options = [
         """The layout of the directory structure. 'standard' installs files to
            several subdirectories under 'prefix', for example, 'prefix/bin',
            'prefix/include/cantera', 'prefix/lib' etc. This layout is best used in
-           conjunction with "prefix='/usr/local'". 'compact' puts all installed
-           files in the subdirectory defined by 'prefix'. This layout is best
-           with a prefix like '/opt/cantera'. 'debian' installs to the stage
-           directory in a layout used for generating Debian packages.""",
+           conjunction with "prefix='/usr/local'". 'compact' puts all installed files
+           in the subdirectory defined by 'prefix'. This layout is best with a prefix
+           like '/opt/cantera'. 'debian' installs to the stage directory in a layout
+           used for generating Debian packages. If the Python executable found during
+           compilation is managed by 'conda', the layout will default to 'conda'
+           irrespective of operating system. For the 'conda' layout, the Python package
+           as well as all libraries and header files are installed into the active
+           'conda' environment. Input data, samples, and other files are installed in
+           the 'shared/cantera' subdirectory of the active 'conda' environment.""",
         {"Windows": "compact", "default": "standard"},
-        ("standard", "compact", "debian")),
+        ("standard", "compact", "debian", "conda")),
     BoolOption(
         "fast_fail_tests",
         "If enabled, tests will exit at the first failure.",
@@ -866,10 +879,10 @@ except subprocess.CalledProcessError:
     env["git_commit"] = "unknown"
 
 # Print values of all build options:
-print("Configuration variables read from 'cantera.conf' and command line:")
-for line in open('cantera.conf'):
-    print('   ', line.strip())
-print()
+# the (updated) "cantera.conf" combines all options that were specified by the user
+cantera_conf = Path("cantera.conf").read_text()
+logger.info("Configuration variables read from 'cantera.conf' and command line:")
+logger.info(textwrap.indent(cantera_conf, "    "), print_level=False)
 
 # ********************************************
 # *** Configure system-specific properties ***
@@ -905,6 +918,19 @@ if os.pathsep == ';':
 env['extra_inc_dirs'] = [d for d in env['extra_inc_dirs'].split(os.pathsep) if d]
 env['extra_lib_dirs'] = [d for d in env['extra_lib_dirs'].split(os.pathsep) if d]
 
+# Add conda library/include paths (if applicable) to extra
+conda_prefix = os.environ.get("CONDA_PREFIX")
+if conda_prefix is not None:
+    if os.name == "nt":
+        conda_inc_dir = pjoin(conda_prefix, "Library", "include")
+        conda_lib_dir = pjoin(conda_prefix, "Library", env["libdirname"])
+    else:
+        conda_inc_dir = pjoin(conda_prefix, "include")
+        conda_lib_dir = pjoin(conda_prefix, env["libdirname"])
+    env["extra_inc_dirs"].append(conda_inc_dir)
+    env["extra_lib_dirs"].append(conda_lib_dir)
+    logger.info(f"Adding conda include and library paths: {conda_prefix}")
+
 env.Append(CPPPATH=env['extra_inc_dirs'],
            LIBPATH=env['extra_lib_dirs'])
 
@@ -1626,26 +1652,65 @@ if env['matlab_toolbox'] == 'y':
 # /usr/local because of dist-packages vs site-packages
 env['debian'] = any(name.endswith('dist-packages') for name in sys.path)
 
+# Identify options selected either on command line or in cantera.conf
+selected_options = set(line.split("=")[0].strip()
+    for line in cantera_conf.splitlines())
+
+# Check whether Cantera should be installed into a conda environment
+if conda_prefix is not None:
+    if env["layout"] != "conda" and sys.executable.startswith(conda_prefix):
+        # use conda layout unless any 'blocking' options were specified
+        blocking_options = {"layout", "prefix", "python_prefix", "python_cmd"}
+        if not selected_options & blocking_options:
+            env["layout"] = "conda"
+            logger.info(
+                f"Using conda environment as default 'prefix': {conda_prefix}")
+elif env["layout"] == "conda":
+    logger.error("Layout option 'conda' requires a conda environment.")
+    sys.exit(1)
+
 # Directories where things will be after actually being installed. These
 # variables are the ones that are used to populate header files, scripts, etc.
-env['prefix'] = os.path.normpath(env['prefix'])
-env['ct_installroot'] = env['prefix']
-env['ct_libdir'] = pjoin(env['prefix'], env['libdirname'])
-env['ct_bindir'] = pjoin(env['prefix'], 'bin')
-env['ct_incdir'] = pjoin(env['prefix'], 'include', 'cantera')
-env['ct_incroot'] = pjoin(env['prefix'], 'include')
+if env["layout"] == "conda":
+    if "stage_dir" in selected_options:
+        conda_prefix = Path(conda_prefix)
+        env["prefix"] = str(conda_prefix.relative_to(conda_prefix.parents[2]))
+    else:
+        env["prefix"] = os.path.normpath(conda_prefix)
+
+if env["layout"] == "conda" and os.name == "nt":
+    env["ct_libdir"] = pjoin(env["prefix"], "Library", env["libdirname"])
+    env["ct_bindir"] = pjoin(env["prefix"], "Scripts")
+    env["ct_python_bindir"] = pjoin(env["prefix"], "Scripts")
+    env["ct_incdir"] = pjoin(env["prefix"], "Library", "include", "cantera")
+    env["ct_incroot"] = pjoin(env["prefix"], "Library", "include")
+else:
+    env["prefix"] = os.path.normpath(env["prefix"])
+    env["ct_libdir"] = pjoin(env["prefix"], env["libdirname"])
+    env["ct_bindir"] = pjoin(env["prefix"], "bin")
+    env["ct_python_bindir"] = pjoin(env["prefix"], "bin")
+    env["ct_incdir"] = pjoin(env["prefix"], "include", "cantera")
+    env["ct_incroot"] = pjoin(env["prefix"], "include")
+
+env["ct_installroot"] = env["prefix"]
 
 if env['layout'] == 'compact':
     env['ct_datadir'] = pjoin(env['prefix'], 'data')
     env['ct_sampledir'] = pjoin(env['prefix'], 'samples')
+    env["ct_docdir"] = pjoin(env["prefix"], "doc")
     env['ct_mandir'] = pjoin(env['prefix'], 'man1')
     env['ct_matlab_dir'] = pjoin(env['prefix'], 'matlab', 'toolbox')
 else:
     env['ct_datadir'] = pjoin(env['prefix'], 'share', 'cantera', 'data')
     env['ct_sampledir'] = pjoin(env['prefix'], 'share', 'cantera', 'samples')
+    env["ct_docdir"] = pjoin(env["prefix"], "share", "cantera", "doc")
     env['ct_mandir'] = pjoin(env['prefix'], 'share', 'man', 'man1')
-    env['ct_matlab_dir'] = pjoin(env['prefix'], env['libdirname'],
-                                 'cantera', 'matlab', 'toolbox')
+    if env["layout"] == "conda":
+        env["ct_matlab_dir"] = pjoin(
+            env["prefix"], "share", "cantera", "matlab", "toolbox")
+    else:
+        env["ct_matlab_dir"] = pjoin(
+            env["prefix"], env["libdirname"], "cantera", "matlab", "toolbox")
 
 # Always set the stage directory before building an MSI installer
 if 'msi' in COMMAND_LINE_TARGETS:
@@ -1673,7 +1738,7 @@ if env["stage_dir"]:
     if stage_prefix.is_absolute():
         stage_prefix = Path(*stage_prefix.parts[1:])
 
-    instRoot = Path.cwd().joinpath(env["stage_dir"], stage_prefix)
+    instRoot = str(Path.cwd().joinpath(env["stage_dir"], stage_prefix))
 else:
     instRoot = env["prefix"]
 
@@ -1684,6 +1749,7 @@ if os.path.abspath(instRoot) == Dir('.').abspath:
 
 if env['layout'] == 'debian':
     base = pjoin(os.getcwd(), 'debian')
+    env["inst_root"] = base
 
     env['inst_libdir'] = pjoin(base, 'cantera-dev', 'usr', env['libdirname'])
     env['inst_incdir'] = pjoin(base, 'cantera-dev', 'usr', 'include', 'cantera')
@@ -1701,25 +1767,11 @@ if env['layout'] == 'debian':
     env['inst_python_bindir'] = pjoin(base, 'cantera-python', 'usr', 'bin')
     env['python_prefix'] = pjoin(base, 'cantera-python3')
 else:
-    env['inst_libdir'] = pjoin(instRoot, env['libdirname'])
-    env['inst_bindir'] = pjoin(instRoot, 'bin')
-    env['inst_python_bindir'] = pjoin(instRoot, 'bin')
-    env['inst_incdir'] = pjoin(instRoot, 'include', 'cantera')
-    env['inst_incroot'] = pjoin(instRoot, 'include')
-
-    if env['layout'] == 'compact':
-        env['inst_matlab_dir'] = pjoin(instRoot, 'matlab', 'toolbox')
-        env['inst_datadir'] = pjoin(instRoot, 'data')
-        env['inst_sampledir'] = pjoin(instRoot, 'samples')
-        env['inst_docdir'] = pjoin(instRoot, 'doc')
-        env['inst_mandir'] = pjoin(instRoot, 'man1')
-    else: # env['layout'] == 'standard'
-        env['inst_matlab_dir'] = pjoin(instRoot, env['libdirname'], 'cantera',
-                                       'matlab', 'toolbox')
-        env['inst_datadir'] = pjoin(instRoot, 'share', 'cantera', 'data')
-        env['inst_sampledir'] = pjoin(instRoot, 'share', 'cantera', 'samples')
-        env['inst_docdir'] = pjoin(instRoot, 'share', 'cantera', 'doc')
-        env['inst_mandir'] = pjoin(instRoot, 'share', 'man', 'man1')
+    env["inst_root"] = instRoot
+    locations = ["libdir", "bindir", "python_bindir", "incdir", "incroot",
+        "matlab_dir", "datadir", "sampledir", "docdir", "mandir"]
+    for loc in locations:
+        env[f"inst_{loc}"] = env[f"ct_{loc}"].replace(env["ct_installroot"], instRoot)
 
 # **************************************
 # *** Set options needed in config.h ***