| # This is a configuration file for devtools (`mojo_run`, `mojo_test) running | 
 | # within a Mojo checkout. | 
 |  | 
 | # The content has to parse to a Python dictionary literal. Strings of the form | 
 | # '@{ABC}' are aliases that will be substituted for their values before | 
 | # evaluation: | 
 | #  '@{BUILD_DIR}': path to the output directory | 
 |  | 
 | { | 
 |   # Each dev server will be configured as specified and mapped for the | 
 |   # indicated host using --map-origin. | 
 |   'dev_servers': [ | 
 |     { | 
 |       'host': 'https://core.mojoapps.io/', | 
 |       # At this port the server will appear to the shell. That means actually | 
 |       # running on this port when running a Linux shell and being forwarded from | 
 |       # this port when running on Android. Using a fixed port enables caching | 
 |       # server responses between shell runs. | 
 |       'port': 31839, | 
 |       # First matching prefix will apply. Within the directiories specified for | 
 |       # a prefix, first location that contains the requested path will apply. | 
 |       'mappings': [ | 
 |         ('packages/', ['@{BUILD_DIR}/gen/dart-pkg/packages']), | 
 |         ('', [ | 
 |           # We map two directiories, so that both exploded dart apps under | 
 |           # checkout root and built apps in the build directory are available. | 
 |           # For example, one could refer to the apps of either type using urls: | 
 |           #  - https://core.mojoapps.io/spinning_cube.mojo | 
 |           #  - https://core.mojoapps.io/examples/dart/device_info/main.dart | 
 |           '@{BUILD_DIR}', | 
 |           '.' | 
 |         ]), | 
 |       ], | 
 |     }, | 
 |   ], | 
 | } |