Attempt to synthesize a controller based on existing controllers. This is useful to create a controller when a user specifies a path to an entry in the BROWSER environment variable -- we can copy a general controller to operate using a specific installation of the desired browser in
(browser, *, preferred=False)
| 113 | |
| 114 | |
| 115 | def _synthesize(browser, *, preferred=False): |
| 116 | """Attempt to synthesize a controller based on existing controllers. |
| 117 | |
| 118 | This is useful to create a controller when a user specifies a path to |
| 119 | an entry in the BROWSER environment variable -- we can copy a general |
| 120 | controller to operate using a specific installation of the desired |
| 121 | browser in this way. |
| 122 | |
| 123 | If we can't create a controller in this way, or if there is no |
| 124 | executable for the requested browser, return [None, None]. |
| 125 | |
| 126 | """ |
| 127 | cmd = browser.split()[0] |
| 128 | if not shutil.which(cmd): |
| 129 | return [None, None] |
| 130 | name = os.path.basename(cmd) |
| 131 | try: |
| 132 | command = _browsers[name.lower()] |
| 133 | except KeyError: |
| 134 | return [None, None] |
| 135 | # now attempt to clone to fit the new name: |
| 136 | controller = command[1] |
| 137 | if controller and name.lower() == controller.basename: |
| 138 | import copy |
| 139 | controller = copy.copy(controller) |
| 140 | controller.name = browser |
| 141 | controller.basename = os.path.basename(browser) |
| 142 | register(browser, None, instance=controller, preferred=preferred) |
| 143 | return [None, controller] |
| 144 | return [None, None] |
| 145 | |
| 146 | |
| 147 | # General parent classes |