[patch v5 6/6] lib: Add regexp searching for mid: prefix

[David Bremner]

The bulk of the change is passing in the field options to the regexp
field processor, so that we can properly handle the
fallback (non-regexp case).
---
 lib/database.cc      | 11 +++++++----
 lib/regexp-fields.cc | 28 +++++++++++++++++++++-------
 lib/regexp-fields.h  |  4 +++-
 3 files changed, 31 insertions(+), 12 deletions(-)

diff --git a/lib/database.cc b/lib/database.cc
index 21c8c5f2..5f02d218 100644
--- a/lib/database.cc
+++ b/lib/database.cc
@@ -262,7 +262,8 @@ prefix_t prefix_table[] = {
     { "tag",			"K",		NOTMUCH_FIELD_EXTERNAL },
     { "is",			"K",		NOTMUCH_FIELD_EXTERNAL },
     { "id",			"Q",		NOTMUCH_FIELD_EXTERNAL },
-    { "mid",			"Q",		NOTMUCH_FIELD_EXTERNAL },
+    { "mid",			"Q",		NOTMUCH_FIELD_EXTERNAL |
+						NOTMUCH_FIELD_PROCESSOR },
     { "path",			"P",		NOTMUCH_FIELD_EXTERNAL },
     { "property",		"XPROPERTY",	NOTMUCH_FIELD_EXTERNAL },
     /*
@@ -294,16 +295,17 @@ prefix_t prefix_table[] = {
 
 #if HAVE_XAPIAN_FIELD_PROCESSOR
 static Xapian::FieldProcessor *
-_make_field_processor (const char *name, notmuch_database_t *notmuch) {
+_make_field_processor (const char *name, notmuch_field_flag_t options,
+		       notmuch_database_t *notmuch) {
     if (STRNCMP_LITERAL (name, "date") == 0)
 	return (new DateFieldProcessor())->release ();
     else if (STRNCMP_LITERAL(name, "query") == 0)
 	return (new QueryFieldProcessor (*notmuch->query_parser, notmuch))->release ();
     else
-	return (new RegexpFieldProcessor (name, *notmuch->query_parser, notmuch))->release ();
+	return (new RegexpFieldProcessor (name, options, *notmuch->query_parser, notmuch))->release ();
 }
 #else
-#define _make_field_processor(name, db) NULL
+#define _make_field_processor(name, options, db) NULL
 #endif
 
 const char *
@@ -1069,6 +1071,7 @@ notmuch_database_open_verbose (const char *path,
 		if (HAVE_XAPIAN_FIELD_PROCESSOR &&
 		    (prefix->flags & NOTMUCH_FIELD_PROCESSOR)) {
 		    Xapian::FieldProcessor *fp = _make_field_processor (prefix->name,
+									prefix->flags,
 									notmuch);
 
 		    notmuch->query_parser->add_boolean_prefix (prefix->name, fp);
diff --git a/lib/regexp-fields.cc b/lib/regexp-fields.cc
index b2b39504..a32b965e 100644
--- a/lib/regexp-fields.cc
+++ b/lib/regexp-fields.cc
@@ -114,13 +114,21 @@ static inline Xapian::valueno _find_slot (std::string prefix)
 	return NOTMUCH_VALUE_FROM;
     else if (prefix == "subject")
 	return NOTMUCH_VALUE_SUBJECT;
+    else if (prefix == "mid")
+	return NOTMUCH_VALUE_MESSAGE_ID;
     else
 	throw Xapian::QueryParserError ("unsupported regexp field '" + prefix + "'");
 }
 
-RegexpFieldProcessor::RegexpFieldProcessor (std::string prefix, Xapian::QueryParser &parser_, notmuch_database_t *notmuch_)
-	: slot (_find_slot (prefix)), term_prefix (_find_prefix (prefix.c_str ())),
-	  parser (parser_), notmuch (notmuch_)
+RegexpFieldProcessor::RegexpFieldProcessor (std::string prefix,
+					    notmuch_field_flag_t options_,
+					    Xapian::QueryParser &parser_,
+					    notmuch_database_t *notmuch_)
+	: slot (_find_slot (prefix)),
+	  term_prefix (_find_prefix (prefix.c_str ())),
+	  options (options_),
+	  parser (parser_),
+	  notmuch (notmuch_)
 {
 };
 
@@ -135,10 +143,16 @@ RegexpFieldProcessor::operator() (const std::string & str)
 	    throw Xapian::QueryParserError ("unmatch regex delimiter in '" + str + "'");
 	}
     } else {
-	/* TODO replace this with a nicer API level triggering of
-	 * phrase parsing, when possible */
-	std::string quoted='"' + str + '"';
-	return parser.parse_query (quoted, NOTMUCH_QUERY_PARSER_FLAGS, term_prefix);
+	if (options & NOTMUCH_FIELD_PROBABILISTIC) {
+	    /* TODO replace this with a nicer API level triggering of
+	     * phrase parsing, when possible */
+	    std::string quoted='"' + str + '"';
+	    return parser.parse_query (quoted, NOTMUCH_QUERY_PARSER_FLAGS, term_prefix);
+	} else {
+	    /* Boolean prefix */
+	    std::string term = term_prefix + str;
+	    return Xapian::Query (term);
+	}
     }
 }
 #endif
diff --git a/lib/regexp-fields.h b/lib/regexp-fields.h
index bac11999..8a0e72e1 100644
--- a/lib/regexp-fields.h
+++ b/lib/regexp-fields.h
@@ -63,11 +63,13 @@ class RegexpFieldProcessor : public Xapian::FieldProcessor {
  protected:
     Xapian::valueno slot;
     std::string term_prefix;
+    int options;
     Xapian::QueryParser &parser;
     notmuch_database_t *notmuch;
 
  public:
-    RegexpFieldProcessor (std::string prefix, Xapian::QueryParser &parser_, notmuch_database_t *notmuch_);
+    RegexpFieldProcessor (std::string prefix, notmuch_field_flag_t options,
+			  Xapian::QueryParser &parser_, notmuch_database_t *notmuch_);
 
     ~RegexpFieldProcessor () { };
 
-- 
2.11.0