Download iamcal's sprite sheets during provisioning and generate CSS files.

Add code to download iamcal's sprite sheets and generate CSS files required
for displaying these sprite sheets using emoji's unicode codepoints rather
than their names.

tools/setup/emoji/build_emoji

@@ -2,7 +2,7 @@
 #
 # See docs/emoji.md for a high-level explanation of how this system
 # works.
-from __future__ import print_function
+from __future__ import division, print_function
 import os
 import glob
 import shutil
@@ -54,6 +54,32 @@ if (typeof module !== 'undefined') {
 }
 """
 
+SPRITE_CSS_FILE_TEMPLATE = """\
+div.emoji,
+span.emoji
+{
+    display: inline-block;
+    background-image: url('sheet_google_32.png');
+    -webkit-background-size: 1025px 1025px;
+    -moz-background-size: 1025px 1025px;
+    background-size: 1025px 1025px;
+    background-repeat: no-repeat;
+
+    /* Hide the text. */
+    text-indent: 100%%;
+    white-space: nowrap;
+    overflow: hidden;
+}
+
+%(emoji_positions)s
+"""
+
+EMOJI_POS_INFO_TEMPLATE = """\
+.emoji-%(codepoint)s {
+    background-position: %(pos_x)s%% %(pos_y)s%%;
+}
+"""
+
 # change directory
 os.chdir(EMOJI_SCRIPT_DIR_PATH)
 
@@ -239,6 +265,20 @@ def dump_emojis(cache_path):
             os.path.join(cache_emoji, fn)
         )
 
+    sprite_sheet_google = os.path.join(EMOJI_DATA_PATH, 'sheet_google_32.png')
+    run(['cp', sprite_sheet_google, cache_path], shell=True)
+    emoji_positions = ""
+    for emoji in emoji_data:
+        if emoji["has_img_google"]:
+            emoji_positions += EMOJI_POS_INFO_TEMPLATE % {'codepoint': emoji['unified'],
+                                                          'pos_x': (emoji["sheet_x"] * 100) / 40,
+                                                          'pos_y': (emoji["sheet_y"] * 100) / 40,
+                                                          }
+    SPRITE_CSS_PATH = os.path.join(cache_path, 'google_sprite.css')
+    sprite_css_file = open(SPRITE_CSS_PATH, 'w')
+    sprite_css_file.write(SPRITE_CSS_FILE_TEMPLATE % {'emoji_positions': emoji_positions, })
+    sprite_css_file.close()
+
     # Add zulip emoji to `emoji_map` so that we can avoid
     # adding unnecessary exceptions to the rendering logic.
     emoji_map['zulip'] = 'zulip'

tools/setup/emoji/download-emoji-data

@@ -16,8 +16,9 @@ else
 fi
 
 if [ "$CURRENT_COMMIT" == "$COMMIT" ]; then
-    echo "Already at latest version of emoji.json"
+    echo "Already at latest version of iamcal's dataset."
 else
     echo "$COMMIT" > "$COMMIT_FILE_PATH"
     wget "https://raw.githubusercontent.com/iamcal/emoji-data/$COMMIT/emoji_pretty.json" -O "$OUTPUT_PATH/emoji.json"
+    wget "https://raw.githubusercontent.com/iamcal/emoji-data/$COMMIT/sheet_google_32.png" -O "$OUTPUT_PATH/sheet_google_32.png"
 fi

version.py

@@ -1,2 +1,2 @@
 ZULIP_VERSION = "1.5.1+git"
-PROVISION_VERSION = '4.15'
+PROVISION_VERSION = '4.16'