Merge branch 'liw/assuming'

8 files changed, 95 insertions, 27 deletions

diff --git a/NEWS b/NEWS
index ac47c61..cb4584d 100644
--- a/NEWS
+++ b/NEWS
@@ -11,6 +11,7 @@ Version 0.X, released UNRELEASED
   includes a shell library when running any IMPLEMENTS section.
 * FINALLY always worked in yarn, but has now been added to the manual
   page as well.
+* The keyword ASSUMING has been added to yarn.
 * New yarn option `--run` allows running selected tests only.
 * New yarn option `--snapshot` makes snapshots of the test working
   directory after each step in a scenario. Combined with the, also
diff --git a/README.yarn b/README.yarn
index 49fcd62..76d57b5 100644
--- a/README.yarn
+++ b/README.yarn
@@ -99,7 +99,7 @@ The following keywords are defined.
 * **ASSUMING** defines a condition for the scenario. The rest of the
   line is "matched text", which gets implemented by an
   IMPLEMENTS section. If the code executed by the implementation
-  fails, the scenario is skipped. (NOT yet implemented.)
+  fails, the scenario is skipped.
 
 * **GIVEN** prepares the world for the test to run. If
   the implementation fails, the scenario fails.
diff --git a/yarn b/yarn
index fb6e5a3..6845345 100755
--- a/yarn
+++ b/yarn
@@ -22,6 +22,7 @@ import logging
 import os
 import re
 import shutil
+import sys
 import tempfile
 import time
 import ttystatus
@@ -225,36 +226,47 @@ class YarnRunner(cliapp.Application):
         os.mkdir(datadir)
         self.info('DATADIR is %s' % datadir)
 
+        assuming = [s for s in scenario.steps if s.what == 'ASSUMING']
         cleanup = [s for s in scenario.steps if s.what == 'FINALLY']
-        normal = [s for s in scenario.steps if s not in cleanup]
+        normal = [s for s in scenario.steps if s not in assuming + cleanup]
 
         ok = True
         step_number = 0
 
-        for step in normal:
-            exit = self.run_step(datadir, scenario, step, shell_prelude)
+        for step in assuming:
+            exit = self.run_step(datadir, scenario, step, shell_prelude, False)
             step_number += 1
             self.snapshot_datadir(
                 tempdir, datadir, scenario, step_number, step)
             if exit != 0:
-                ok = False
-                break
-
-        for step in cleanup:
-            exit = self.run_step(datadir, scenario, step, shell_prelude)
-            step_number += 1
-            self.snapshot_datadir(
-                tempdir, datadir, scenario, step_number, step)
-            if exit != 0:
-                ok = False
                 break
+        else:
+            for step in normal:
+                exit = self.run_step(
+                    datadir, scenario, step, shell_prelude, True)
+                step_number += 1
+                self.snapshot_datadir(
+                    tempdir, datadir, scenario, step_number, step)
+                if exit != 0:
+                    ok = False
+                    break
+
+            for step in cleanup:
+                exit = self.run_step(
+                    datadir, scenario, step, shell_prelude, True)
+                step_number += 1
+                self.snapshot_datadir(
+                    tempdir, datadir, scenario, step_number, step)
+                if exit != 0:
+                    ok = False
+                    break
 
         if not self.settings['snapshot']:
             shutil.rmtree(tempdir)
 
         return ok
 
-    def run_step(self, datadir, scenario, step, shell_prelude):
+    def run_step(self, datadir, scenario, step, shell_prelude, report_error):
         self.info('Running step "%s %s"' % (step.what, step.text))
         self.ts['step'] = step
         self.ts['step_name'] = '%s %s' % (step.what, step.text)
@@ -281,7 +293,7 @@ class YarnRunner(cliapp.Application):
         else:
             logging.debug('Standard error: empty')
 
-        if exit != 0:
+        if exit != 0 and report_error:
             self.error(
                 'ERROR: In scenario "%s"\nstep "%s %s" failed,\n'
                 'with exit code %d:\n'
diff --git a/yarn.tests/assuming-failure.script b/yarn.tests/assuming-failure.script
new file mode 100755
index 0000000..f630294
--- /dev/null
+++ b/yarn.tests/assuming-failure.script
@@ -0,0 +1,23 @@
+#!/bin/sh
+
+set -eu
+
+
+cat <<EOF > "$DATADIR/test.yarn"
+    SCENARIO    foo
+    ASSUMING    something
+    THEN        remember
+    FINALLY     cleanup
+
+    IMPLEMENTS ASSUMING something
+    false
+    IMPLEMENTS THEN remember
+    touch "$DATADIR/then-flag"
+    IMPLEMENTS FINALLY cleanup
+    touch "$DATADIR/cleanup-flag"
+EOF
+
+./yarn -q "$DATADIR/test.yarn"
+[ ! -e "$DATADIR/then-flag" ]
+[ ! -e "$DATADIR/cleanup-flag" ]
+
diff --git a/yarn.tests/assuming.script b/yarn.tests/assuming.script
new file mode 100755
index 0000000..9471280
--- /dev/null
+++ b/yarn.tests/assuming.script
@@ -0,0 +1,23 @@
+#!/bin/sh
+
+set -eu
+
+
+cat <<EOF > "$DATADIR/test.yarn"
+    SCENARIO    foo
+    ASSUMING    something
+    THEN        remember
+    FINALLY     cleanup
+
+    IMPLEMENTS ASSUMING something
+    true
+    IMPLEMENTS THEN remember
+    touch "$DATADIR/then-flag"
+    IMPLEMENTS FINALLY cleanup
+    touch "$DATADIR/cleanup-flag"
+EOF
+
+./yarn -q "$DATADIR/test.yarn"
+[ -e "$DATADIR/then-flag" ]
+[ -e "$DATADIR/cleanup-flag" ]
+
diff --git a/yarn.tests/setup b/yarn.tests/setup
new file mode 100755
index 0000000..d64c24e
--- /dev/null
+++ b/yarn.tests/setup
@@ -0,0 +1,3 @@
+#!/bin/sh
+
+find "$DATADIR" -mindepth 1 -delete
diff --git a/yarnlib/block_parser.py b/yarnlib/block_parser.py
index 84074e2..64dc990 100644
--- a/yarnlib/block_parser.py
+++ b/yarnlib/block_parser.py
@@ -36,6 +36,7 @@ class BlockParser(object):
         self.implementations = []
         self.line_parsers = {
             'SCENARIO': self.parse_scenario,
+            'ASSUMING': self.parse_assuming,
             'GIVEN': self.parse_given,
             'WHEN': self.parse_when,
             'THEN': self.parse_then,
@@ -86,6 +87,9 @@ class BlockParser(object):
         self.scenarios[-1].steps.append(step)
         return blocks
 
+    def parse_assuming(self, line, blocks):
+        return self.parse_simple('ASSUMING', line, blocks)
+
     def parse_given(self, line, blocks):
         return self.parse_simple('GIVEN', line, blocks)
 
diff --git a/yarnlib/block_parser_tests.py b/yarnlib/block_parser_tests.py
index c988479..78754b5 100644
--- a/yarnlib/block_parser_tests.py
+++ b/yarnlib/block_parser_tests.py
@@ -32,7 +32,7 @@ class BlockParserTests(unittest.TestCase):
 
     def test_parses_simple_elements(self):
         self.parser.parse_blocks(
-            ['SCENARIO foo', 'GIVEN bar',
+            ['SCENARIO foo', 'ASSUMING something', 'GIVEN bar',
              'WHEN foobar\nTHEN yoyo\nFINALLY yay\nAND yeehaa'])
 
         self.assertEqual(len(self.parser.scenarios), 1)
@@ -40,17 +40,19 @@ class BlockParserTests(unittest.TestCase):
 
         scenario = self.parser.scenarios[0]
         self.assertEqual(scenario.name, 'foo')
-        self.assertEqual(len(scenario.steps), 5)
-        self.assertEqual(scenario.steps[0].what, 'GIVEN')
-        self.assertEqual(scenario.steps[0].text, 'bar')
-        self.assertEqual(scenario.steps[1].what, 'WHEN')
-        self.assertEqual(scenario.steps[1].text, 'foobar')
-        self.assertEqual(scenario.steps[2].what, 'THEN')
-        self.assertEqual(scenario.steps[2].text, 'yoyo')
-        self.assertEqual(scenario.steps[3].what, 'FINALLY')
-        self.assertEqual(scenario.steps[3].text, 'yay')
+        self.assertEqual(len(scenario.steps), 6)
+        self.assertEqual(scenario.steps[0].what, 'ASSUMING')
+        self.assertEqual(scenario.steps[0].text, 'something')
+        self.assertEqual(scenario.steps[1].what, 'GIVEN')
+        self.assertEqual(scenario.steps[1].text, 'bar')
+        self.assertEqual(scenario.steps[2].what, 'WHEN')
+        self.assertEqual(scenario.steps[2].text, 'foobar')
+        self.assertEqual(scenario.steps[3].what, 'THEN')
+        self.assertEqual(scenario.steps[3].text, 'yoyo')
         self.assertEqual(scenario.steps[4].what, 'FINALLY')
-        self.assertEqual(scenario.steps[4].text, 'yeehaa')
+        self.assertEqual(scenario.steps[4].text, 'yay')
+        self.assertEqual(scenario.steps[5].what, 'FINALLY')
+        self.assertEqual(scenario.steps[5].text, 'yeehaa')
 
     def test_normalises_whitespace(self):
         self.parser.parse_blocks(['SCENARIO   foo   bar   '])