diff options
author | 2014-08-28 13:19:38 -0700 | |
---|---|---|
committer | 2014-08-28 13:29:43 -0700 | |
commit | b92a09d5e7e3334312265cc718c2d4d4dc687bb7 (patch) | |
tree | 8869607c92db25d8548ecda48ef381e9a005abac | |
parent | 02a07164f34462b8ce7c26594746ae587206a96e (diff) |
Fix the assertion failure in expand_variables()
expand_variables() is slightly confused about how to handle last_idx. On
input, it expects it to be the index to start processing at, but when
called recursively it always passes the current index. This means that
it may sometimes pass an index 1 past the end of the input string.
Notably, that happens when typing something like
> echo "$foo
(where "foo" is any string that is not a prefix of some existing
variable name)
Fix this by explicitly defining last_idx as being the last processed
index, meaning the next index to process is actually last_idx-1. This
means we should call it with next.size() instead of next.size()-1.
-rw-r--r-- | expand.cpp | 23 |
1 files changed, 14 insertions, 9 deletions
@@ -1051,22 +1051,27 @@ static size_t parse_slice(const wchar_t *in, wchar_t **end_ptr, std::vector<long and do proper testing afterwards. This function operates on strings backwards, starting at last_idx. + + Note: last_idx is considered to be where it previously finished + procesisng. This means it actually starts operating on last_idx-1. + As such, to process a string fully, pass string.size() as last_idx + instead of string.size()-1. */ static int expand_variables(parser_t &parser, const wcstring &instr, std::vector<completion_t> &out, long last_idx, parse_error_list_t *errors) { - // We permit last_idx to be beyond the end of the string if and only if the string is empty - assert(instr.empty() || (last_idx >= 0 && (size_t)last_idx < instr.size())); - - // Make this explicit - if (instr.empty()) + const size_t insize = instr.size(); + + // last_idx may be 1 past the end of the string, but no further + assert(last_idx >= 0 && (size_t)last_idx <= insize); + + if (last_idx == 0) { append_completion(out, instr); return true; } - + bool is_ok = true; bool empty = false; - const size_t insize = instr.size(); wcstring var_tmp; @@ -1078,7 +1083,7 @@ static int expand_variables(parser_t &parser, const wcstring &instr, std::vector // CHECK( out, 0 ); - for (long i=last_idx; (i>=0) && is_ok && !empty; i--) + for (long i=last_idx-1; (i>=0) && is_ok && !empty; i--) { const wchar_t c = instr.at(i); if ((c == VARIABLE_EXPAND) || (c == VARIABLE_EXPAND_SINGLE)) @@ -1809,7 +1814,7 @@ int expand_string(const wcstring &input, std::vector<completion_t> &output, expa } else { - if (!expand_variables(parser, next, *out, next.size() - 1, errors)) + if (!expand_variables(parser, next, *out, next.size(), errors)) { return EXPAND_ERROR; } |