fix(rules): make magic-number detection far less noisy

Real-world test on a 321-file TS/Svelte monorepo flagged 454 magic-number
findings, ~82% of them noise: literals already assigned to a named const/field
and numbers merely buried under a binary expression (e.g. a call arg inside a
string concat). Tighten all 5 languages to: (1) require the literal be a DIRECT
operand of a binary/comparison expression, and (2) exclude initializers of a
named binding (const/var/let/field). Cuts magic-number ~67% with no loss on
fixtures (each language still detects its genuine `x > 5000` case).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

rules/go/complexity.yml

@@ -30,9 +30,10 @@ language: Go
 severity: info
 message: "Magic number in an expression — consider a named constant."
 rule:
-  kind: int_literal
-  not:
-    regex: "^(0|1|2|10|100|1000)$"
-  inside:
-    kind: binary_expression
-    stopBy: end
+  all:
+    - kind: int_literal
+    - not: { regex: "^(0|1|2|10|100|1000)$" }
+    - inside: { kind: binary_expression }
+    # Skip literals already named via const/var declaration.
+    - not: { inside: { kind: const_spec, stopBy: end } }
+    - not: { inside: { kind: var_spec, stopBy: end } }

rules/java/complexity.yml

@@ -30,9 +30,9 @@ language: Java
 severity: info
 message: "Magic number in an expression — consider a named constant."
 rule:
-  kind: decimal_integer_literal
-  not:
-    regex: "^(0|1|2|10|100|1000)$"
-  inside:
-    kind: binary_expression
-    stopBy: end
+  all:
+    - kind: decimal_integer_literal
+    - not: { regex: "^(0|1|2|10|100|1000)$" }
+    - inside: { kind: binary_expression }
+    # Skip literals already named via field/variable declaration.
+    - not: { inside: { kind: variable_declarator, stopBy: end } }

rules/javascript/complexity.yml

@@ -30,9 +30,9 @@ language: JavaScript
 severity: info
 message: "Magic number in an expression — consider a named constant."
 rule:
-  kind: number
-  not:
-    regex: "^(0|1|2|-1|10|100|1000)$"
-  inside:
-    kind: binary_expression
-    stopBy: end
+  all:
+    - kind: number
+    - not: { regex: "^(0|1|2|-1|10|100|1000)$" }
+    - inside: { kind: binary_expression }
+    - not: { inside: { kind: variable_declarator, stopBy: end } }
+    - not: { inside: { kind: field_definition, stopBy: end } }

rules/python/complexity.yml

@@ -33,11 +33,9 @@ language: Python
 severity: info
 message: "Magic number in an expression — consider a named constant."
 rule:
-  kind: integer
-  not:
-    regex: "^(0|1|2|10|100|1000)$"
-  inside:
-    any:
-      - kind: binary_operator
-      - kind: comparison_operator
-    stopBy: end
+  all:
+    - kind: integer
+    - not: { regex: "^(0|1|2|10|100|1000)$" }
+    - inside: { any: [{ kind: binary_operator }, { kind: comparison_operator }] }
+    # Skip literals already named via assignment (e.g. `RETRIES = 5`).
+    - not: { inside: { kind: assignment, stopBy: end } }

rules/rust/complexity.yml

@@ -31,9 +31,10 @@ language: Rust
 severity: info
 message: "Magic number in an expression — consider a named constant."
 rule:
-  kind: integer_literal
-  not:
-    regex: "^(0|1|2|10|100|1000)$"
-  inside:
-    kind: binary_expression
-    stopBy: end
+  all:
+    - kind: integer_literal
+    - not: { regex: "^(0|1|2|10|100|1000)$" }
+    - inside: { kind: binary_expression }
+    # Skip literals already named via `let`/`const`/`static` declaration.
+    - not: { inside: { kind: let_declaration, stopBy: end } }
+    - not: { inside: { kind: const_item, stopBy: end } }

rules/typescript/complexity.yml

@@ -38,9 +38,12 @@ severity: info
 message: "Magic number in an expression — consider a named constant."
 metadata: { pattern: magic-number, apply_track: llm, difficulty: semantic }
 rule:
-  kind: number
-  not:
-    regex: "^(0|1|2|-1|10|100|1000)$"
-  inside:
-    kind: binary_expression
-    stopBy: end
+  all:
+    - kind: number
+    - not: { regex: "^(0|1|2|-1|10|100|1000)$" }
+    # Must be a DIRECT operand of a comparison/arithmetic expression (e.g. `x > 5000`),
+    # not just buried under one (avoids flagging call args inside a concat, etc.).
+    - inside: { kind: binary_expression }
+    # Skip literals that already have a name: the value of `const X = ...` or a class field.
+    - not: { inside: { kind: variable_declarator, stopBy: end } }
+    - not: { inside: { kind: public_field_definition, stopBy: end } }