Merge pull request #1098 from sirosen/non-standalone-exit

Allow non-standalone ctx.exit() calls to return values rather than call sys.exit()

CHANGES.rst

@@ -8,6 +8,8 @@ Version 7.0
 
 (upcoming release with new features, release date to be decided)
 
+- Non-standalone calls to Context.exit return the exit code, rather than
+  calling ``sys.exit`` (`#667`_)(`#533`_)
 - Updated test env matrix. (`#1027`_)
 - Fixes a ``ZeroDivisionError`` in ``ProgressBar.make_step``,
   when the arg passed to the first call of ``ProgressBar.update`` is 0. (`#1012`_)(`#447`_)

click/core.py

@@ -9,7 +9,7 @@
 from .types import convert_type, IntRange, BOOL
 from .utils import make_str, make_default_short_help, echo, get_os_args
 from .exceptions import ClickException, UsageError, BadParameter, Abort, \
-     MissingParameter
+     MissingParameter, Exit
 from .termui import prompt, confirm, style
 from .formatting import HelpFormatter, join_options
 from .parser import OptionParser, split_opt
@@ -498,7 +498,7 @@ def abort(self):
 
     def exit(self, code=0):
         """Exits the application with a given exit code."""
-        sys.exit(code)
+        raise Exit(code)
 
     def get_usage(self):
         """Helper method to get formatted usage string for the current
@@ -714,6 +714,13 @@ def main(self, args=None, prog_name=None, complete_var=None,
                     rv = self.invoke(ctx)
                     if not standalone_mode:
                         return rv
+                    # it's not safe to `ctx.exit(rv)` here!
+                    # note that `rv` may actually contain data like "1" which
+                    # has obvious effects
+                    # more subtle case: `rv=[None, None]` can come out of
+                    # chained commands which all returned `None` -- so it's not
+                    # even always obvious that `rv` indicates success/failure
+                    # by its truthiness/falsiness
                     ctx.exit()
             except (EOFError, KeyboardInterrupt):
                 echo(file=sys.stderr)
@@ -728,6 +735,19 @@ def main(self, args=None, prog_name=None, complete_var=None,
                     sys.exit(1)
                 else:
                     raise
+        except Exit as e:
+            if standalone_mode:
+                sys.exit(e.exit_code)
+            else:
+                # in non-standalone mode, return the exit code
+                # note that this is only reached if `self.invoke` above raises
+                # an Exit explicitly -- thus bypassing the check there which
+                # would return its result
+                # the results of non-standalone execution may therefore be
+                # somewhat ambiguous: if there are codepaths which lead to
+                # `ctx.exit(1)` and to `return 1`, the caller won't be able to
+                # tell the difference between the two
+                return e.exit_code
         except Abort:
             if not standalone_mode:
                 raise

click/exceptions.py

@@ -223,3 +223,13 @@ def format_message(self):
 
 class Abort(RuntimeError):
     """An internal signalling exception that signals Click to abort."""
+
+
+class Exit(RuntimeError):
+    """An exception that indicates that the application should exit with some
+    status code.
+
+    :param code: the status code to exit with.
+    """
+    def __init__(self, code=0):
+        self.exit_code = code

tests/test_context.py

@@ -193,6 +193,7 @@ def test_close_before_pop(runner):
     @click.pass_context
     def cli(ctx):
         ctx.obj = 'test'
+
         @ctx.call_on_close
         def foo():
             assert click.get_current_context().obj == 'test'
@@ -239,3 +240,19 @@ def test2(ctx, foo):
     result = runner.invoke(cli, ['test2'])
     assert not result.exception
     assert result.output == 'foocmd\n'
+
+
+def test_exit_not_standalone():
+    @click.command()
+    @click.pass_context
+    def cli(ctx):
+        ctx.exit(1)
+
+    assert cli.main([], 'test_exit_not_standalone', standalone_mode=False) == 1
+
+    @click.command()
+    @click.pass_context
+    def cli(ctx):
+        ctx.exit(0)
+
+    assert cli.main([], 'test_exit_not_standalone', standalone_mode=False) == 0

tests/test_testing.py

@@ -153,16 +153,34 @@ def cli_string():
         click.echo('hello world')
         sys.exit('error')
 
+    @click.command()
+    @click.pass_context
+    def cli_string_ctx_exit(ctx):
+        click.echo('hello world')
+        ctx.exit('error')
+
     @click.command()
     def cli_int():
         click.echo('hello world')
         sys.exit(1)
 
+    @click.command()
+    @click.pass_context
+    def cli_int_ctx_exit(ctx):
+        click.echo('hello world')
+        ctx.exit(1)
+
     @click.command()
     def cli_float():
         click.echo('hello world')
         sys.exit(1.0)
 
+    @click.command()
+    @click.pass_context
+    def cli_float_ctx_exit(ctx):
+        click.echo('hello world')
+        ctx.exit(1.0)
+
     @click.command()
     def cli_no_error():
         click.echo('hello world')
@@ -173,14 +191,26 @@ def cli_no_error():
     assert result.exit_code == 1
     assert result.output == 'hello world\nerror\n'
 
+    result = runner.invoke(cli_string_ctx_exit)
+    assert result.exit_code == 1
+    assert result.output == 'hello world\nerror\n'
+
     result = runner.invoke(cli_int)
     assert result.exit_code == 1
     assert result.output == 'hello world\n'
 
+    result = runner.invoke(cli_int_ctx_exit)
+    assert result.exit_code == 1
+    assert result.output == 'hello world\n'
+
     result = runner.invoke(cli_float)
     assert result.exit_code == 1
     assert result.output == 'hello world\n1.0\n'
 
+    result = runner.invoke(cli_float_ctx_exit)
+    assert result.exit_code == 1
+    assert result.output == 'hello world\n1.0\n'
+
     result = runner.invoke(cli_no_error)
     assert result.exit_code == 0
     assert result.output == 'hello world\n'