Factor and simplify generation of the lookup trie used for HTMLLookupTrie.

third_party/WebKit/Source/build/scripts/templates/macros.tmpl

 {#
     FIXME: Do we need to put license blocks in generated files?
 #}
 {% macro license() %}
 // Copyright (c) 2014 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.
 {%- endmacro %}
+
+
+{% macro trie_leaf(index, object, return_macro, lowercase_data) %}
+{% for name, value in object.items() %}
+    {% if name|length %}
+if (
+        {%- for c in name -%}
+            {%- if lowercase_data -%}
+    {{ " && " if not loop.first }}toASCIILower(data[{{index + loop.index0}}]) == '{{c}}'
+            {%- else -%}
+    {{ " && " if not loop.first }}data[{{index + loop.index0}}] == '{{c}}'
+            {%- endif -%}
+        {%- endfor -%}
+    )
+    return {{ return_macro(value) }};
+break;
+    {% else %}
+return {{ return_macro(value) }};
+    {% endif %}
+{% endfor %}
+{% endmacro %}
+
+
+{% macro trie_switch(trie, index, return_macro, lowercase_data) %}

[Timothy Loh, 2016/05/13 04:49:17]

Do you think it would be clearer to merge the macros, something like as follows
(sorry for typing out a code block, thought it might be faster since you're away
soon):

(I also changed foo.items()[0][1] to foo.values()[0], the for-loop over 1 item
to just use set, and moved the break -- the other macro will need to write break
too)

{% if trie|length == 1 and trie.values()[0] is string %}
    {% set name, value = trie.items()[0] %}
    {% if name|length %}
if (
        {%- for c in name -%} 
            {%- if lowercase_data -%} 
    {{ " && " if not loop.first }}toASCIILower(data[{{index + loop.index0}}]) ==
'{{c}}'
            {%- else -%} 
    {{ " && " if not loop.first }}data[{{index + loop.index0}}] == '{{c}}'
            {%- endif -%} 
        {%- endfor -%} 
    )   
    return {{ return_macro(value) }}; 
break;
    {% else %}
return {{ return_macro(value) }}; 
    {% endif %}
{% else %}
{% if lowercase_data %}
switch (toASCIILower(data[{{index}}])) {
{% else %}
switch (data[{{index}}]) {
{% endif %}
{% for char, value in trie.items()|sort %}
case '{{char}}':
    {{ trie_switch(value, index + 1, return_macro, lowercase_data) | indent(4)
}}
    break;
{% endfor %}
}
{% endif %}
{% endmacro %}

[meade_UTC10, 2016/05/13 06:48:20]

Hmm, I think it's clearer to have the trie_leaf macro, but I moved the check for
whether to call it up to the top of trie_switch. What do you think of this?

+{% if lowercase_data %}
+switch (toASCIILower(data[{{index}}])) {
+{% else %}
+switch (data[{{index}}]) {
+{% endif %}
+{% for char, value in trie.items()|sort %}
+case '{{char}}':
+    {% if value|length == 1 and value.items()[0][1] is string %}
+    {{ trie_leaf(index+1, value, return_macro, lowercase_data) | indent(4) }}
+    {% else %}
+    {{ trie_switch(value, index + 1, return_macro, lowercase_data) | indent(4) }}
+    {% endif %}
+{% endfor %}
+}
+break;
+{% endmacro %}
+
+
+{% macro trie_length_switch(length_tries, return_macro, default_return_value, lowercase_data) %}

[Timothy Loh, 2016/05/13 05:41:33]

default_return_value isn't used any more

[meade_UTC10, 2016/05/13 06:48:20]

Done.

+switch(length) {

[Timothy Loh, 2016/05/13 04:49:17]

Space after switch

[meade_UTC10, 2016/05/13 06:48:20]

Done.

+{% for length, trie in length_tries %}
+case {{ length }}:
+    {{ trie_switch(trie, 0, return_macro, lowercase_data) | indent(4) }}
+{% endfor %}
+}
+{% endmacro %}