Add interactive tests for abbreviations

tests/pexpects/abbrs.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python3
+from pexpect_helper import SpawnedProc
+
+import re
+
+sp = SpawnedProc()
+send, sendline, sleep, expect_prompt, expect_re, expect_str = (
+    sp.send,
+    sp.sendline,
+    sp.sleep,
+    sp.expect_prompt,
+    sp.expect_re,
+    sp.expect_str,
+)
+expect_prompt()
+
+# ? prints the command line, bracketed by <>, then clears it.
+sendline(r"""bind '?' 'echo "<$(commandline)>"; commandline ""'; """)
+expect_prompt()
+
+# Basic test.
+sendline(r"abbr alpha beta")
+expect_prompt()
+
+send(r"alpha ?")
+expect_str(r"<beta >")
+
+# Default abbreviations expand only in command position.
+send(r"echo alpha ?")
+expect_str(r"<echo alpha >")
+
+# Abbreviation expansions may have multiple words.
+sendline(r"abbr --add emacsnw emacs -nw")
+expect_prompt()
+send(r"emacsnw ?")
+expect_str(r"<emacs -nw >")
+
+# Regression test that abbreviations still expand in incomplete positions.
+sendline(r"""abbr --erase (abbr --list)""")
+expect_prompt()
+sendline(r"""abbr --add foo echo bar""")
+expect_prompt()
+sendline(r"if foo")
+expect_str(r"if echo bar")
+sendline(r"end")
+expect_prompt(r"bar")
+
+# Regression test that 'echo (' doesn't hang.
+sendline(r"echo )")
+expect_str(r"Unexpected ')' for unopened parenthesis")
+send(r"?")
+expect_str(r"<echo )>")