swig: add smoke tests (#23662)

var/spack/repos/builtin/packages/swig/package.py

@@ -70,3 +70,45 @@ def create_symlink(self):
         @when(_version)
         def autoreconf(self, spec, prefix):
             which('sh')('./autogen.sh')
+
+    @property
+    def _installed_exe(self):
+        return join_path(self.prefix, 'bin', 'swig')
+
+    def _test_version(self):
+        version = str(self.version)
+        if version.endswith('-fortran'):
+            version = version.replace('-', r'\+')
+        elif version in ('fortran', 'master'):
+            version = r'.*'
+
+        self.run_test(self._installed_exe,
+                      '-version',
+                      expected=[r'SWIG Version {0}'.format(version)],
+                      purpose="test: version")
+
+    def _test_swiglib(self):
+        # Get SWIG's alleged path to library files
+        swig = Executable(self._installed_exe)
+        swiglib = swig('-swiglib', output=str).strip()
+
+        # Check that the lib dir exists
+        if not os.path.isdir(swiglib):
+            msg = "SWIG library does not exist at '{0}'".format(swiglib)
+            self.test_failures.append([None, msg])
+
+        # Check for existence of other critical SWIG library files
+        swigfile = join_path(swiglib, 'swig.swg')
+        if not os.path.exists(swigfile):
+            msg = "SWIG runtime does not exist at '{0}'".format(swigfile)
+            self.test_failures.append([None, msg])
+        if 'fortran' in str(self.version):
+            swigfile = join_path(swiglib, 'fortran', 'fortran.swg')
+            if not os.path.exists(swigfile):
+                msg = "SWIG+Fortran runtime does not exist at '{0}'".format(
+                    swigfile)
+                self.test_failures.append([None, msg])
+
+    def test(self):
+        self._test_version()
+        self._test_swiglib()