add cache

CLAUDE.md

@@ -106,7 +106,7 @@ which Django itself enforces while it parses the template ("add requires 2 argum
 ### First-party libraries
 
 Django ships `i18n`, `l10n`, `static`, `cache` and `tz` as libraries rather than builtins. Their tags are
-modelled as ordinary tags (so far: `static`, `l10n`, `tz`), and the grammar **never requires the `{% load %}`**, because
+modelled as ordinary tags (so far: `static`, `l10n`, `tz`, `cache`), and the grammar **never requires the `{% load %}`**, because
 an engine can preload a library through `OPTIONS: {"builtins": [...]}`, which makes `{% static "a" %}` valid
 with no load at all.
 
@@ -205,5 +205,10 @@ documentation or memory. Both checks are worth repeating whenever tags, filters
   bits from the end, so `{% static "a" junk %}` and `{% static "a" as u v %}` are accepted there and
   rejected here, and `PrefixNode.handle_token` raises `IndexError` rather than `TemplateSyntaxError` on
   `{% get_static_prefix as %}`.
+- Django's `{% cache %}` takes its fragment name as the raw word in that position and finds the cache to
+  use by testing whether the last word starts with `using=`, and only when something precedes it. So
+  `{% cache 500 sidebar.name %}` names a fragment there, `{% cache 500 using="c" %}` names a fragment
+  called `using="c"` rather than choosing a cache, and `{% cache 500 sidebar using= %}` takes an empty
+  name. All three are errors here.
 - `partial`/`partialdef` are Django builtins as of Django 6; `elif`/`else`/`empty` are modelled as parts of
   their enclosing tag rather than as separate tags.

grammar.js

@@ -247,6 +247,7 @@ const NAMES_INSIDE_A_TAG_GROUP = [
   "empty",
   "endautoescape",
   "endblock",
+  "endcache",
   "endcomment",
   "endfilter",
   "endfor",
@@ -378,6 +379,7 @@ const django = grammar({
       choice(
         $.autoescape_group,
         $.block_group,
+        $.cache_group,
         $.comment_group,
         $.csp_nonce_attr,
         $.csrf_token,
@@ -461,6 +463,18 @@ const django = grammar({
         optional($.template),
         block("endblock", $.pop_block),
       ),
+    cache_group: ($) =>
+      seq(
+        block(
+          "cache",
+          part($.filtered_value),
+          part(choice($.identifier, $.string)),
+          repeat(part($.filtered_value)),
+          optional(part(seq("using=", $.filtered_value))),
+        ),
+        optional($.template),
+        block("endcache"),
+      ),
     comment_group: ($) =>
       seq(
         block("comment", optional(part($.string))),

queries/highlights.scm

@@ -50,6 +50,8 @@ tag: [
     ("endautoescape")
     ("block")
     ("endblock")
+    ("cache")
+    ("endcache")
     ("comment")
     ("endcomment")
     ("csp_nonce_attr")

queries/libraries.scm

@@ -24,6 +24,9 @@
 (get_media_prefix
   tag: ("get_media_prefix") @library.static)
 
+(cache_group
+  tag: ("cache") @library.cache)
+
 (localize_group
   tag: ("localize") @library.l10n)
 

src/grammar.json

@@ -542,6 +542,10 @@
           "type": "SYMBOL",
           "name": "block_group"
         },
+        {
+          "type": "SYMBOL",
+          "name": "cache_group"
+        },
         {
           "type": "SYMBOL",
           "name": "comment_group"
@@ -1293,6 +1297,194 @@
         }
       ]
     },
+    "cache_group": {
+      "type": "SEQ",
+      "members": [
+        {
+          "type": "SEQ",
+          "members": [
+            {
+              "type": "STRING",
+              "value": "{%"
+            },
+            {
+              "type": "CHOICE",
+              "members": [
+                {
+                  "type": "PATTERN",
+                  "value": "[ \\t\\r\\n]+"
+                },
+                {
+                  "type": "BLANK"
+                }
+              ]
+            },
+            {
+              "type": "FIELD",
+              "name": "tag",
+              "content": {
+                "type": "STRING",
+                "value": "cache"
+              }
+            },
+            {
+              "type": "SEQ",
+              "members": [
+                {
+                  "type": "PATTERN",
+                  "value": "[ \\t\\r\\n]+"
+                },
+                {
+                  "type": "SYMBOL",
+                  "name": "filtered_value"
+                }
+              ]
+            },
+            {
+              "type": "SEQ",
+              "members": [
+                {
+                  "type": "PATTERN",
+                  "value": "[ \\t\\r\\n]+"
+                },
+                {
+                  "type": "CHOICE",
+                  "members": [
+                    {
+                      "type": "SYMBOL",
+                      "name": "identifier"
+                    },
+                    {
+                      "type": "SYMBOL",
+                      "name": "string"
+                    }
+                  ]
+                }
+              ]
+            },
+            {
+              "type": "REPEAT",
+              "content": {
+                "type": "SEQ",
+                "members": [
+                  {
+                    "type": "PATTERN",
+                    "value": "[ \\t\\r\\n]+"
+                  },
+                  {
+                    "type": "SYMBOL",
+                    "name": "filtered_value"
+                  }
+                ]
+              }
+            },
+            {
+              "type": "CHOICE",
+              "members": [
+                {
+                  "type": "SEQ",
+                  "members": [
+                    {
+                      "type": "PATTERN",
+                      "value": "[ \\t\\r\\n]+"
+                    },
+                    {
+                      "type": "SEQ",
+                      "members": [
+                        {
+                          "type": "STRING",
+                          "value": "using="
+                        },
+                        {
+                          "type": "SYMBOL",
+                          "name": "filtered_value"
+                        }
+                      ]
+                    }
+                  ]
+                },
+                {
+                  "type": "BLANK"
+                }
+              ]
+            },
+            {
+              "type": "CHOICE",
+              "members": [
+                {
+                  "type": "PATTERN",
+                  "value": "[ \\t\\r\\n]+"
+                },
+                {
+                  "type": "BLANK"
+                }
+              ]
+            },
+            {
+              "type": "STRING",
+              "value": "%}"
+            }
+          ]
+        },
+        {
+          "type": "CHOICE",
+          "members": [
+            {
+              "type": "SYMBOL",
+              "name": "template"
+            },
+            {
+              "type": "BLANK"
+            }
+          ]
+        },
+        {
+          "type": "SEQ",
+          "members": [
+            {
+              "type": "STRING",
+              "value": "{%"
+            },
+            {
+              "type": "CHOICE",
+              "members": [
+                {
+                  "type": "PATTERN",
+                  "value": "[ \\t\\r\\n]+"
+                },
+                {
+                  "type": "BLANK"
+                }
+              ]
+            },
+            {
+              "type": "FIELD",
+              "name": "tag",
+              "content": {
+                "type": "STRING",
+                "value": "endcache"
+              }
+            },
+            {
+              "type": "CHOICE",
+              "members": [
+                {
+                  "type": "PATTERN",
+                  "value": "[ \\t\\r\\n]+"
+                },
+                {
+                  "type": "BLANK"
+                }
+              ]
+            },
+            {
+              "type": "STRING",
+              "value": "%}"
+            }
+          ]
+        }
+      ]
+    },
     "comment_group": {
       "type": "SEQ",
       "members": [
@@ -5423,6 +5615,10 @@
         "type": "STRING",
         "value": "endblock"
       },
+      {
+        "type": "STRING",
+        "value": "endcache"
+      },
       {
         "type": "STRING",
         "value": "endcomment"

src/node-types.json

@@ -11,6 +11,10 @@
         "type": "block_group",
         "named": true
       },
+      {
+        "type": "cache_group",
+        "named": true
+      },
       {
         "type": "comment_group",
         "named": true
@@ -246,6 +250,48 @@
       ]
     }
   },
+  {
+    "type": "cache_group",
+    "named": true,
+    "fields": {
+      "tag": {
+        "multiple": true,
+        "required": true,
+        "types": [
+          {
+            "type": "cache",
+            "named": false
+          },
+          {
+            "type": "endcache",
+            "named": false
+          }
+        ]
+      }
+    },
+    "children": {
+      "multiple": true,
+      "required": true,
+      "types": [
+        {
+          "type": "filtered_value",
+          "named": true
+        },
+        {
+          "type": "identifier",
+          "named": true
+        },
+        {
+          "type": "string",
+          "named": true
+        },
+        {
+          "type": "template",
+          "named": true
+        }
+      ]
+    }
+  },
   {
     "type": "comment_group",
     "named": true,
@@ -1928,6 +1974,10 @@
     "type": "by",
     "named": false
   },
+  {
+    "type": "cache",
+    "named": false
+  },
   {
     "type": "capfirst",
     "named": false
@@ -2028,6 +2078,10 @@
     "type": "endblock",
     "named": false
   },
+  {
+    "type": "endcache",
+    "named": false
+  },
   {
     "type": "endcomment",
     "named": false
@@ -2448,6 +2502,10 @@
     "type": "urlizetrunc",
     "named": false
   },
+  {
+    "type": "using=",
+    "named": false
+  },
   {
     "type": "utc",
     "named": false

test/corpus/cache.txt

@@ -0,0 +1,235 @@
+==================
+Cache
+==================
+
+{% cache 500 sidebar %}x{% endcache %}
+
+---
+
+(template
+  (content)
+  (cache_group
+    (filtered_value
+      (value
+        (literal
+          (number))))
+    (identifier)
+    (template
+      (content)))
+  (content))
+
+==================
+Cache With A Variable Timeout
+==================
+
+{% cache t sidebar %}x{% endcache %}
+
+---
+
+(template
+  (content)
+  (cache_group
+    (filtered_value
+      (value
+        (variable_attribute
+          (identifier))))
+    (identifier)
+    (template
+      (content)))
+  (content))
+
+==================
+Cache With A Filtered Timeout
+==================
+
+{% cache 500|add:1 sidebar %}x{% endcache %}
+
+---
+
+(template
+  (content)
+  (cache_group
+    (filtered_value
+      (value
+        (literal
+          (number)))
+      (filter_expression
+        (filter
+          argument: (value
+            (literal
+              (number))))))
+    (identifier)
+    (template
+      (content)))
+  (content))
+
+==================
+Cache With A Quoted Fragment Name
+==================
+
+{% cache 500 "sidebar" %}x{% endcache %}
+
+---
+
+(template
+  (content)
+  (cache_group
+    (filtered_value
+      (value
+        (literal
+          (number))))
+    (string)
+    (template
+      (content)))
+  (content))
+
+==================
+Cache Varying On Arguments
+==================
+
+{% cache 500 sidebar a b %}x{% endcache %}
+
+---
+
+(template
+  (content)
+  (cache_group
+    (filtered_value
+      (value
+        (literal
+          (number))))
+    (identifier)
+    (filtered_value
+      (value
+        (variable_attribute
+          (identifier))))
+    (filtered_value
+      (value
+        (variable_attribute
+          (identifier))))
+    (template
+      (content)))
+  (content))
+
+==================
+Cache Varying On A Filtered Argument
+==================
+
+{% cache 500 sidebar a|upper %}x{% endcache %}
+
+---
+
+(template
+  (content)
+  (cache_group
+    (filtered_value
+      (value
+        (literal
+          (number))))
+    (identifier)
+    (filtered_value
+      (value
+        (variable_attribute
+          (identifier)))
+      (filter_expression
+        (filter)))
+    (template
+      (content)))
+  (content))
+
+==================
+Cache Using A Named Cache
+==================
+
+{% cache 500 sidebar using="c" %}x{% endcache %}
+
+---
+
+(template
+  (content)
+  (cache_group
+    (filtered_value
+      (value
+        (literal
+          (number))))
+    (identifier)
+    (filtered_value
+      (value
+        (literal
+          (string))))
+    (template
+      (content)))
+  (content))
+
+==================
+Cache Using An Unquoted Cache Name
+==================
+
+{% cache 500 sidebar using=c %}x{% endcache %}
+
+---
+
+(template
+  (content)
+  (cache_group
+    (filtered_value
+      (value
+        (literal
+          (number))))
+    (identifier)
+    (filtered_value
+      (value
+        (variable_attribute
+          (identifier))))
+    (template
+      (content)))
+  (content))
+
+==================
+Cache Without A Fragment Name
+:error
+==================
+
+{% cache 500 %}x{% endcache %}
+
+---
+
+
+==================
+Cache With Anything After Using
+:error
+==================
+
+{% cache 500 sidebar using="c" extra %}x{% endcache %}
+
+---
+
+
+==================
+Cache With An Empty Using
+:error
+==================
+
+{% cache 500 sidebar using= %}x{% endcache %}
+
+---
+
+
+==================
+Cache With An Attribute Fragment Name
+:error
+==================
+
+{% cache 500 sidebar.name %}x{% endcache %}
+
+---
+
+
+==================
+Cache With Using As Its Fragment Name
+:error
+==================
+
+{% cache 500 using="c" %}x{% endcache %}
+
+---