Issue #18725: The textwrap module now supports truncating multiline text.

1 files changed, 98 insertions, 7 deletions

diff --git a/Lib/test/test_textwrap.py b/Lib/test/test_textwrap.py
index 36c15cc..1bba77e 100644
--- a/Lib/test/test_textwrap.py
+++ b/Lib/test/test_textwrap.py
@@ -42,10 +42,6 @@ class BaseTestCase(unittest.TestCase):
                          "\nexpected %r\n"
                          "but got  %r" % (expect, result))
 
-    def check_shorten(self, text, width, expect, **kwargs):
-        result = shorten(text, width, **kwargs)
-        self.check(result, expect)
-
 
 class WrapTestCase(BaseTestCase):
 
@@ -433,6 +429,90 @@ What a mess!
         self.check_wrap(text, 7, ["aa \xe4\xe4-", "\xe4\xe4"])
 
 
+class MaxLinesTestCase(BaseTestCase):
+    text = "Hello there, how are you this fine day?  I'm glad to hear it!"
+
+    def test_simple(self):
+        self.check_wrap(self.text, 12,
+                        ["Hello [...]"],
+                        max_lines=0)
+        self.check_wrap(self.text, 12,
+                        ["Hello [...]"],
+                        max_lines=1)
+        self.check_wrap(self.text, 12,
+                        ["Hello there,",
+                         "how [...]"],
+                        max_lines=2)
+        self.check_wrap(self.text, 13,
+                        ["Hello there,",
+                         "how are [...]"],
+                        max_lines=2)
+        self.check_wrap(self.text, 80, [self.text], max_lines=1)
+        self.check_wrap(self.text, 12,
+                        ["Hello there,",
+                         "how are you",
+                         "this fine",
+                         "day?  I'm",
+                         "glad to hear",
+                         "it!"],
+                        max_lines=6)
+
+    def test_spaces(self):
+        # strip spaces before placeholder
+        self.check_wrap(self.text, 12,
+                        ["Hello there,",
+                         "how are you",
+                         "this fine",
+                         "day? [...]"],
+                        max_lines=4)
+        # placeholder at the start of line
+        self.check_wrap(self.text, 6,
+                        ["Hello",
+                         "[...]"],
+                        max_lines=2)
+        # final spaces
+        self.check_wrap(self.text + ' ' * 10, 12,
+                        ["Hello there,",
+                         "how are you",
+                         "this fine",
+                         "day?  I'm",
+                         "glad to hear",
+                         "it!"],
+                        max_lines=6)
+
+    def test_placeholder(self):
+        self.check_wrap(self.text, 12,
+                        ["Hello..."],
+                        max_lines=1,
+                        placeholder='...')
+        self.check_wrap(self.text, 12,
+                        ["Hello there,",
+                         "how are..."],
+                        max_lines=2,
+                        placeholder='...')
+        # long placeholder and indentation
+        with self.assertRaises(ValueError):
+            wrap(self.text, 16, initial_indent='    ',
+                 max_lines=1, placeholder=' [truncated]...')
+        with self.assertRaises(ValueError):
+            wrap(self.text, 16, subsequent_indent='    ',
+                 max_lines=2, placeholder=' [truncated]...')
+        self.check_wrap(self.text, 16,
+                        ["    Hello there,",
+                         "  [truncated]..."],
+                        max_lines=2,
+                        initial_indent='    ',
+                        subsequent_indent='  ',
+                        placeholder=' [truncated]...')
+        self.check_wrap(self.text, 16,
+                        ["  [truncated]..."],
+                        max_lines=1,
+                        initial_indent='  ',
+                        subsequent_indent='    ',
+                        placeholder=' [truncated]...')
+        self.check_wrap(self.text, 80, [self.text], placeholder='.' * 1000)
+
+
 class LongWordTestCase (BaseTestCase):
     def setUp(self):
         self.wrapper = TextWrapper()
@@ -493,6 +573,14 @@ How *do* you spell that odd word, anyways?
         result = wrap(self.text, width=30, break_long_words=0)
         self.check(result, expect)
 
+    def test_max_lines_long(self):
+        self.check_wrap(self.text, 12,
+                        ['Did you say ',
+                         '"supercalifr',
+                         'agilisticexp',
+                         '[...]'],
+                        max_lines=4)
+
 
 class IndentTestCases(BaseTestCase):
 
@@ -782,6 +870,10 @@ class IndentTestCase(unittest.TestCase):
 
 class ShortenTestCase(BaseTestCase):
 
+    def check_shorten(self, text, width, expect, **kwargs):
+        result = shorten(text, width, **kwargs)
+        self.check(result, expect)
+
     def test_simple(self):
         # Simple case: just words, spaces, and a bit of punctuation
         text = "Hello there, how are you this fine day? I'm glad to hear it!"
@@ -825,10 +917,9 @@ class ShortenTestCase(BaseTestCase):
         self.check_shorten("hello      world!  ", 10, "[...]")
 
     def test_width_too_small_for_placeholder(self):
-        wrapper = TextWrapper(width=8)
-        wrapper.shorten("x" * 20, placeholder="(......)")
+        shorten("x" * 20, width=8, placeholder="(......)")
         with self.assertRaises(ValueError):
-            wrapper.shorten("x" * 20, placeholder="(.......)")
+            shorten("x" * 20, width=8, placeholder="(.......)")
 
     def test_first_word_too_long_but_placeholder_fits(self):
         self.check_shorten("Helloo", 5, "[...]")