Add the main lexer logic

Author: sudo-jarvis

jsonschema_lexer/__init__.py

@@ -1,3 +1 @@
-"""
-Fill me in!
-"""
+from .lexer import JSONSchemaLexer # type: ignore

jsonschema_lexer/lexer.py

@@ -0,0 +1,183 @@
+from pygments.lexer import include, RegexLexer
+from pygments.token import Token
+
+def _get_regex_from_options(options: list[str]) -> str:
+    """
+    Constructs a regular expression pattern allowing any string from the options list.
+
+    Args:
+        options (list[str]): List of options to be included in the regex pattern.
+
+    Returns:
+        str: Regular expression pattern constructed from the options.
+    """
+    options = ['"' + option + '"' for option in options]
+    regex_str = "(" + "|".join(options) + ")"
+    return regex_str
+
+class JSONSchemaLexer(RegexLexer):
+    """
+    Lexer for JSON Schema syntax highlighting.
+    """
+    name = "JSON Schema Lexer"
+        
+    data_types = ["object", "integer", "string", "number", "array", "boolean", "null"]
+    core_keywords = [
+        r"\$schema",
+        r"\$id",
+        r"\$ref",
+        r"\$defs",
+        r"\$comment",
+        r"\$dynamicAnchor",
+        r"\$dynamicRef",
+        r"\$anchor",
+        r"\$vocabulary",
+    ]
+    applicator_keywords = [
+        "oneOf",
+        "allOf",
+        "anyOf",
+        "if",
+        "then",
+        "else",
+        "not",
+        "properties",
+        "patternProperties",
+        "additionalProperties",
+        "dependentSchemas",
+        "propertyNames",
+        "prefixNames",
+        "contains",
+        "items",
+    ]
+    meta_data_keywords = [
+        "title",
+        "description",
+        "default",
+        "deprecated",
+        "examples",
+        "readOnly",
+        "writeOnly",
+    ]
+    validation_keywords = [
+        "type",
+        "enum",
+        "const",
+        "minLength",
+        "maxLength",
+        "pattern",
+        "maximum",
+        "exclusiveMinimum",
+        "multipleOf",
+        "exclusiveMaximum",
+        "minimum",
+        "dependentRequired",
+        "minProperties",
+        "maxProperties",
+        "required",
+        "minItems",
+        "maxItems",
+        "minContains",
+        "maxContains",
+        "uniqueItems",
+    ]
+    other_keywords = ["format", "unevaluated", "content", "format_assertion"]
+
+    tokens = {
+        "whitespace": [
+            (r"\s+", Token.Whitespace),
+        ],
+        "data_types": [
+            # Used Literal type here to differentiate the highlighted color of data types from other keywords
+            (_get_regex_from_options(data_types), Token.Literal),
+        ],
+        "core_keywords": [
+            (
+                _get_regex_from_options(core_keywords),
+                Token.Keyword.Reserved,
+                "objectattribute",
+            ),
+        ],
+        "applicator_keywords": [
+            (
+                _get_regex_from_options(applicator_keywords),
+                Token.Keyword.Reserved,
+                "objectattribute",
+            ),
+        ],
+        "validation_keywords": [
+            (
+                _get_regex_from_options(validation_keywords),
+                Token.Keyword.Reserved,
+                "objectattribute",
+            ),
+        ],
+        "meta_data_keywords": [
+            (
+                _get_regex_from_options(meta_data_keywords),
+                Token.Keyword.Reserved,
+                "objectattribute",
+            ),
+        ],
+        "other_keywords": [
+            (
+                _get_regex_from_options(other_keywords),
+                Token.Keyword.Reserved,
+                "objectattribute",
+            ),
+        ],
+        "keywords": [
+            include("core_keywords"),
+            include("applicator_keywords"),
+            include("validation_keywords"),
+            include("meta_data_keywords"),
+            include("other_keywords"),
+        ],
+
+        # represents a simple terminal value
+        "simplevalue": [
+            include("data_types"),
+            (r"(true|false)", Token.Number),
+            (r"-?(?:0|[1-9]\d*)(?:\.\d+)?(?:[eE][+-]?\d+)?", Token.Number.Integer),
+            ('"(\\|"|[^"])*"', Token.String.Double),
+        ],
+
+        # the right hand side of an object, after the attribute name
+        "objectattribute": [
+            include("value"),
+            (r":", Token.Punctuation),
+            # comma terminates the attribute but expects more
+            (r",", Token.Punctuation, "#pop"),
+            # a closing bracket terminates the entire object, so pop twice
+            (r"}", Token.Punctuation, ("#pop", "#pop")),
+        ],
+        
+        # a json object - { attr, attr, ... }
+        "objectvalue": [
+            include("whitespace"),
+            include("keywords"),
+            (r'"(\\\\|\\"|[^"])*"', Token.Name.Tag, "objectattribute"),
+            (r"}", Token.Punctuation, "#pop"),
+        ],
+
+        # json array - [ value, value, ... }
+        "arrayvalue": [
+            include("whitespace"),
+            include("value"),
+            (r",", Token.Punctuation),
+            (r"]", Token.Punctuation, "#pop"),
+        ],
+
+        # a json value - either a simple value or a complex value (object or array)
+        "value": [
+            include("whitespace"),
+            include("simplevalue"),
+            (r"{", Token.Punctuation, "objectvalue"),
+            (r"\[", Token.Punctuation, "arrayvalue"),
+        ],
+
+        # the root of a json document whould be a value
+        "root": [
+            include("value"),
+        ],
+    }