Elide long emails in the wrench and profile menus.

ui/base/text/text_elider.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // This file defines utility functions for eliding and formatting UI text.
 
 #ifndef UI_BASE_TEXT_TEXT_ELIDER_H_
 #define UI_BASE_TEXT_TEXT_ELIDER_H_
 #pragma once
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/string16.h"
 #include "ui/base/ui_export.h"
 #include "ui/gfx/font.h"
 #include "unicode/coll.h"
 #include "unicode/uchar.h"
 
 class FilePath;
 class GURL;
 
 namespace ui {
 
 UI_EXPORT extern const char kEllipsis[];
 
+// Elides only the username portion of the |email|, if possible, so that the
+// returned email is at most |available_pixel_width| wide under |font|.

[asvitkine_google, 2012/03/01 20:13:29]

I would suggest having the first sentence describe the overall behavior of the
function. "Elides only the username..." is not the overall behavior - since it
can also elide the domain.

So please change the first sentence to something like "Elides an email address
to fit into |available_pixel_width| using the specified |font|." Then, you can
go into more details about how it's done. (That it prioritizes eliding the
username first before trying to elide the domain name...)

+// If the domain name by itself is already wider than the width available: it is
+// elided in the middle so that it splits the available width equally with
+// the elided username (should the username be short enough that it doesn't
+// require half the available width: the domain will take that extra width).
+// This function guarantees that the string returned will contain at least one
+// character, other than the ellipsis-es, on either side of the '@'. If it is
+// impossible to achieve these requirements: only an ellipsis will be returned.
+UI_EXPORT string16 ElideEmail(const string16& email,
+                              const gfx::Font& font,
+                              int available_pixel_width);
+
 // This function takes a GURL object and elides it. It returns a string
 // which composed of parts from subdomain, domain, path, filename and query.
 // A "..." is added automatically at the end if the elided string is bigger
-// than the available pixel width. For available pixel width = 0, empty
-// string is returned. |languages| is a comma separated list of ISO 639
-// language codes and is used to determine what characters are understood
-// by a user. It should come from |prefs::kAcceptLanguages|.
+// than the |available_pixel_width|. For |available_pixel_width| == 0, a
+// formatted, but un-elided, string is returned. |languages| is a comma
+// separated list of ISO 639 language codes and is used to determine what
+// characters are understood by a user. It should come from
+// |prefs::kAcceptLanguages|.
 //
 // Note: in RTL locales, if the URL returned by this function is going to be
 // displayed in the UI, then it is likely that the string needs to be marked
 // as an LTR string (using base::i18n::WrapStringWithLTRFormatting()) so that it
 // is displayed properly in an RTL context. Please refer to
 // http://crbug.com/6487 for more information.
 UI_EXPORT string16 ElideUrl(const GURL& url,
                             const gfx::Font& font,
                             int available_pixel_width,
                             const std::string& languages);
 
 enum ElideBehavior {
   // Add ellipsis at the end of the string.
   ELIDE_AT_END,
   // Add ellipsis in the middle of the string.
   ELIDE_IN_MIDDLE,
   // Truncate the end of the string.
   TRUNCATE_AT_END
 };
 
-// Elides |text| to fit in |available_pixel_width| according to the specified
-// |elide_behavior|.
+// This function, if the |text| does not fit the |available_pixel_width|, cuts
+// |text| and adds an ellipsis where specified by |elide_behavior|.

[asvitkine_google, 2012/03/01 20:13:29]

I like the previous wording better. If you want, you can still add the second
clarification sentence, but please don't use "we".

[gab, 2012/03/01 21:48:18]

Right, one of the versions of the code I tried yesterday needed to assume that
an empty string was returned, so I added this to the spec to make sure it wasn't
just a side-effect of the current implementation.

Double-checking now, this version doesn't need to make this assumption anymore;
hence I removed this change.

+// If we must elide, but the ellipsis itself doesn't even fit in
+// |available_pixel_width|, this returns an empty string.
 UI_EXPORT string16 ElideText(const string16& text,
                              const gfx::Font& font,
                              int available_pixel_width,
                              ElideBehavior elide_behavior);
 
 // Elide a filename to fit a given pixel width, with an emphasis on not hiding
 // the extension unless we have to. If filename contains a path, the path will
 // be removed if filename doesn't fit into available_pixel_width. The elided
 // filename is forced to have LTR directionality, which means that in RTL UI
 // the elided filename is wrapped with LRE (Left-To-Right Embedding) mark and
@@ skipping 102 matching lines @@
 // Truncates the string to length characters. This breaks the string at
 // the first word break before length, adding the horizontal ellipsis
 // character (unicode character 0x2026) to render ...
 // The supplied string is returned if the string has length characters or
 // less.
 UI_EXPORT string16 TruncateString(const string16& string, size_t length);
 
 }  // namespace ui
 
 #endif  // UI_BASE_TEXT_TEXT_ELIDER_H_