Add whitespace helpers to complete.h/cpp

src/common.cpp

@@ -74,6 +74,13 @@ static volatile bool termsize_valid = false;
 static char *wcs2str_internal(const wchar_t *in, char *out);
 static void debug_shared(const wchar_t msg_level, const wcstring &msg);
 
+const wchar_t *whitespace = L" \t\r\n\v";
+const char *whitespace_narrow = " \t\r\n\v";
+
+bool is_whitespace(const wcstring &input) {
+    return input.find_first_not_of(whitespace);
+}
+
 bool has_working_tty_timestamps = true;
 
 /// Convert a character to its integer equivalent if it is a valid character for the requested base.

src/common.h

@@ -203,6 +203,13 @@ extern const wchar_t *program_name;
 /// the tty.
 extern bool has_working_tty_timestamps;
 
+/// A list of all whitespace characters
+extern const wchar_t *whitespace;
+extern const char *whitespace_narrow;
+
+bool is_whitespace(const wcstring &input);
+inline bool is_whitespace(const wchar_t *input) { return is_whitespace(wcstring(input)); }
+
 /// This macro is used to check that an argument is true. It is a bit like a non-fatal form of
 /// assert. Instead of exiting on failure, the current function is ended at once. The second
 /// parameter is the return value of the current function on failure.