hush: improve ${var#...}, ${var:+...} and ${var/.../...} - handle quoting

dollar_altvalue1 test partially fails: word splitting of unquoted ${var:+...}
is not correct

function                                             old     new   delta
encode_then_expand_vararg                              -     443    +443
expand_one_var                                      1599    1610     +11
parse_stream                                        2756    2753      -3
encode_string                                        250     242      -8
setup_heredoc                                        308     298     -10
expand_and_evaluate_arith                            106      96     -10
encode_then_expand_string                            142     126     -16
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/5 up/down: 454/-47)           Total: 407 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/shell/ash_test/ash-quoting/dollar_altvalue1.tests b/shell/ash_test/ash-quoting/dollar_altvalue1.tests
new file mode 100755
index 0000000..f4dc8ca
--- /dev/null
+++ b/shell/ash_test/ash-quoting/dollar_altvalue1.tests
@@ -0,0 +1,16 @@
+f() { for i; do echo "|$i|"; done; }
+x=a
+
+echo Unquoted b c d
+f ${x:+b c d}
+echo Unquoted "'b c' d"
+f ${x:+'b c' d}
+echo Unquoted '"b c" d'
+f ${x:+"b c" d}
+
+echo Quoted b c d
+f "${x:+b c d}"
+echo Quoted "'b c' d"
+f "${x:+'b c' d}"
+echo Quoted '"b c" d'
+f "${x:+"b c" d}"