Files.app: split query into AND conditioned keywords in metadata search.

BUG=514853
TEST=unit_tests:SearchMetadataTest.*;SearchMetadataSimpleTest.*

Review URL: https://codereview.chromium.org/1321553003

Cr-Commit-Position: refs/heads/master@{#347862}

components/drive/search_metadata.cc

@@ -10,6 +10,9 @@
 #include "base/bind.h"
 #include "base/i18n/string_search.h"
 #include "base/metrics/histogram.h"
+#include "base/strings/string_piece.h"
+#include "base/strings/string_split.h"
+#include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/time/time.h"
 #include "components/drive/drive_api_util.h"
@@ -141,12 +144,13 @@ class HiddenEntryClassifier {
 
 // Used to implement SearchMetadata.
 // Adds entry to the result when appropriate.
-// In particular, if |query| is non-null, only adds files with the name matching
-// the query.
+// In particular, if size of |queries| is larger than 0, only adds files with
+// the name matching the query.
 FileError MaybeAddEntryToResult(
     ResourceMetadata* resource_metadata,
     ResourceMetadata::Iterator* it,
-    base::i18n::FixedPatternStringSearchIgnoringCaseAndAccents* query,
+    const ScopedVector<
+        base::i18n::FixedPatternStringSearchIgnoringCaseAndAccents>& queries,
     const SearchMetadataPredicate& predicate,
     size_t at_most_num_matches,
     HiddenEntryClassifier* hidden_entry_classifier,
@@ -168,7 +172,7 @@ FileError MaybeAddEntryToResult(
   // contain |query| to match the query.
   std::string highlighted;
   if (!predicate.Run(entry) ||
-      (query && !FindAndHighlight(entry.base_name(), query, &highlighted)))
+      !FindAndHighlight(entry.base_name(), queries, &highlighted))
     return FILE_ERROR_OK;
 
   // Hidden entry should not be returned.
@@ -194,8 +198,18 @@ FileError SearchMetadataOnBlockingPool(ResourceMetadata* resource_metadata,
                       ResultCandidateComparator> result_candidates;
 
   // Prepare data structure for searching.
-  base::i18n::FixedPatternStringSearchIgnoringCaseAndAccents query(
-      base::UTF8ToUTF16(query_text));
+  std::vector<base::string16> keywords =
+      base::SplitString(base::UTF8ToUTF16(query_text),
+                        base::StringPiece16(base::kWhitespaceUTF16),
+                        base::TRIM_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
+
+  ScopedVector<base::i18n::FixedPatternStringSearchIgnoringCaseAndAccents>
+      queries;
+  for (const auto& keyword : keywords) {
+    queries.push_back(
+        new base::i18n::FixedPatternStringSearchIgnoringCaseAndAccents(
+            keyword));
+  }
 
   // Prepare an object to filter out hidden entries.
   ResourceEntry mydrive;
@@ -210,9 +224,8 @@ FileError SearchMetadataOnBlockingPool(ResourceMetadata* resource_metadata,
   scoped_ptr<ResourceMetadata::Iterator> it = resource_metadata->GetIterator();
   for (; !it->IsAtEnd(); it->Advance()) {
     FileError error = MaybeAddEntryToResult(
-        resource_metadata, it.get(), query_text.empty() ? NULL : &query,
-        predicate, at_most_num_matches, &hidden_entry_classifier,
-        &result_candidates);
+        resource_metadata, it.get(), queries, predicate, at_most_num_matches,
+        &hidden_entry_classifier, &result_candidates);
     if (error != FILE_ERROR_OK)
       return error;
   }
@@ -253,6 +266,22 @@ void RunSearchMetadataCallback(const SearchMetadataCallback& callback,
                       base::TimeTicks::Now() - start_time);
 }
 
+// Appends substring of |original_text| to |highlighted_text| with highlight.
+void AppendStringWithHighlight(const base::string16& original_text,
+                               size_t start,
+                               size_t length,
+                               bool highlight,
+                               std::string* highlighted_text) {
+  if (highlight)
+    highlighted_text->append("<b>");
+
+  highlighted_text->append(net::EscapeForHTML(
+      base::UTF16ToUTF8(original_text.substr(start, length))));
+
+  if (highlight)
+    highlighted_text->append("</b>");
+}
+
 }  // namespace
 
 void SearchMetadata(
@@ -308,26 +337,45 @@ bool MatchesType(int options, const ResourceEntry& entry) {
 
 bool FindAndHighlight(
     const std::string& text,
-    base::i18n::FixedPatternStringSearchIgnoringCaseAndAccents* query,
+    const ScopedVector<
+        base::i18n::FixedPatternStringSearchIgnoringCaseAndAccents>& queries,
     std::string* highlighted_text) {
-  DCHECK(query);
   DCHECK(highlighted_text);
   highlighted_text->clear();
 
-  base::string16 text16 = base::UTF8ToUTF16(text);
+  // Check text matches with all queries.
   size_t match_start = 0;
   size_t match_length = 0;
-  if (!query->Search(text16, &match_start, &match_length))
-    return false;
 
-  base::string16 pre = text16.substr(0, match_start);
-  base::string16 match = text16.substr(match_start, match_length);
-  base::string16 post = text16.substr(match_start + match_length);
-  highlighted_text->append(net::EscapeForHTML(base::UTF16ToUTF8(pre)));
-  highlighted_text->append("<b>");
-  highlighted_text->append(net::EscapeForHTML(base::UTF16ToUTF8(match)));
-  highlighted_text->append("</b>");
-  highlighted_text->append(net::EscapeForHTML(base::UTF16ToUTF8(post)));
+  base::string16 text16 = base::UTF8ToUTF16(text);
+  std::vector<bool> highlights(text16.size(), false);
+  for (auto* query : queries) {
+    if (!query->Search(text16, &match_start, &match_length))
+      return false;
+
+    std::fill(highlights.begin() + match_start,
+              highlights.begin() + match_start + match_length, true);
+  }
+
+  // Generate highlighted text.
+  size_t start_current_segment = 0;
+
+  for (size_t i = 0; i < text16.size(); ++i) {
+    if (highlights[start_current_segment] == highlights[i])
+      continue;
+
+    AppendStringWithHighlight(
+        text16, start_current_segment, i - start_current_segment,
+        highlights[start_current_segment], highlighted_text);
+
+    start_current_segment = i;
+  }
+
+  DCHECK_GE(text16.size(), start_current_segment);
+  AppendStringWithHighlight(
+      text16, start_current_segment, text16.size() - start_current_segment,
+      highlights[start_current_segment], highlighted_text);
+
   return true;
 }
 

components/drive/search_metadata.h

@@ -7,6 +7,7 @@
 
 #include <string>
 
+#include "base/memory/scoped_vector.h"
 #include "components/drive/file_system_interface.h"
 
 namespace base {
@@ -24,11 +25,12 @@ typedef base::Callback<bool(const ResourceEntry&)> SearchMetadataPredicate;
 
 // Searches the local resource metadata, and returns the entries
 // |at_most_num_matches| that contain |query| in their base names. Search is
-// done in a case-insensitive fashion. The eligible entries are selected based
-// on the given |options|, which is a bit-wise OR of SearchMetadataOptions.
-// |callback| must not be null. Must be called on UI thread. Empty |query|
-// matches any base name. i.e. returns everything. |blocking_task_runner| must
-// be the same one as |resource_metadata| uses.
+// done in a case-insensitive fashion. |query| is splitted into keywords by
+// whitespace. All keywords are considered as AND condition. The eligible
+// entries are selected based on the given |options|, which is a bit-wise OR of
+// SearchMetadataOptions. |callback| must not be null. Must be called on UI
+// thread. Empty |query| matches any base name. i.e. returns everything.
+// |blocking_task_runner| must be the same one as |resource_metadata| uses.
 void SearchMetadata(
     scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
     ResourceMetadata* resource_metadata,
@@ -47,16 +49,18 @@ void SearchMetadata(
 // match with the query. This option can not be used with other options.
 bool MatchesType(int options, const ResourceEntry& entry);
 
-// Finds |query| in |text| while ignoring cases or accents. Cases of non-ASCII
+// Finds |queries| in |text| while ignoring cases or accents. Cases of non-ASCII
 // characters are also ignored; they are compared in the 'Primary Level' of
 // http://userguide.icu-project.org/collation/concepts.
-// Returns true if |query| is found. |highlighted_text| will have the original
+// Returns true if |queries| are found. |highlighted_text| will have the
+// original
 // text with matched portions highlighted with <b> tag (only the first match
 // is highlighted). Meta characters are escaped like &lt;. The original
 // contents of |highlighted_text| will be lost.
 bool FindAndHighlight(
     const std::string& text,
-    base::i18n::FixedPatternStringSearchIgnoringCaseAndAccents* query,
+    const ScopedVector<
+        base::i18n::FixedPatternStringSearchIgnoringCaseAndAccents>& queries,
     std::string* highlighted_text);
 
 }  // namespace internal