Awk interpreter (#15)

* Migrate AWK to interpreter

* more-depth

* async

* more-tests

* lint

* knip

Author: cramforce

src/commands/awk/ast.ts

@@ -0,0 +1,292 @@
+/**
+ * AWK Abstract Syntax Tree Types
+ *
+ * Follows the same discriminated union pattern as the main bash AST.
+ */
+
+// ─── Expressions ───────────────────────────────────────────
+
+export type AwkExpr =
+  | AwkNumberLiteral
+  | AwkStringLiteral
+  | AwkRegexLiteral
+  | AwkFieldRef
+  | AwkVariable
+  | AwkArrayAccess
+  | AwkBinaryOp
+  | AwkUnaryOp
+  | AwkTernaryOp
+  | AwkFunctionCall
+  | AwkAssignment
+  | AwkPreIncrement
+  | AwkPreDecrement
+  | AwkPostIncrement
+  | AwkPostDecrement
+  | AwkGetline
+  | AwkInExpr
+  | AwkTuple;
+
+export interface AwkNumberLiteral {
+  type: "number";
+  value: number;
+}
+
+export interface AwkStringLiteral {
+  type: "string";
+  value: string;
+}
+
+export interface AwkRegexLiteral {
+  type: "regex";
+  pattern: string;
+}
+
+export interface AwkFieldRef {
+  type: "field";
+  index: AwkExpr;
+}
+
+export interface AwkVariable {
+  type: "variable";
+  name: string;
+}
+
+export interface AwkArrayAccess {
+  type: "array_access";
+  array: string;
+  key: AwkExpr;
+}
+
+export interface AwkBinaryOp {
+  type: "binary";
+  operator:
+    | "+"
+    | "-"
+    | "*"
+    | "/"
+    | "%"
+    | "^"
+    | "=="
+    | "!="
+    | "<"
+    | ">"
+    | "<="
+    | ">="
+    | "~"
+    | "!~"
+    | "&&"
+    | "||"
+    | " "; // concatenation
+  left: AwkExpr;
+  right: AwkExpr;
+}
+
+export interface AwkUnaryOp {
+  type: "unary";
+  operator: "!" | "-" | "+";
+  operand: AwkExpr;
+}
+
+export interface AwkPreIncrement {
+  type: "pre_increment";
+  operand: AwkVariable | AwkArrayAccess | AwkFieldRef;
+}
+
+export interface AwkPreDecrement {
+  type: "pre_decrement";
+  operand: AwkVariable | AwkArrayAccess | AwkFieldRef;
+}
+
+export interface AwkPostIncrement {
+  type: "post_increment";
+  operand: AwkVariable | AwkArrayAccess | AwkFieldRef;
+}
+
+export interface AwkPostDecrement {
+  type: "post_decrement";
+  operand: AwkVariable | AwkArrayAccess | AwkFieldRef;
+}
+
+export interface AwkTernaryOp {
+  type: "ternary";
+  condition: AwkExpr;
+  consequent: AwkExpr;
+  alternate: AwkExpr;
+}
+
+export interface AwkFunctionCall {
+  type: "call";
+  name: string;
+  args: AwkExpr[];
+}
+
+export interface AwkAssignment {
+  type: "assignment";
+  operator: "=" | "+=" | "-=" | "*=" | "/=" | "%=" | "^=";
+  target: AwkFieldRef | AwkVariable | AwkArrayAccess;
+  value: AwkExpr;
+}
+
+export interface AwkInExpr {
+  type: "in";
+  key: AwkExpr;
+  array: string;
+}
+
+export interface AwkGetline {
+  type: "getline";
+  variable?: string;
+  file?: AwkExpr;
+}
+
+export interface AwkTuple {
+  type: "tuple";
+  elements: AwkExpr[];
+}
+
+// ─── Statements ────────────────────────────────────────────
+
+export type AwkStmt =
+  | AwkExpressionStmt
+  | AwkPrintStmt
+  | AwkPrintfStmt
+  | AwkIfStmt
+  | AwkWhileStmt
+  | AwkDoWhileStmt
+  | AwkForStmt
+  | AwkForInStmt
+  | AwkBreakStmt
+  | AwkContinueStmt
+  | AwkNextStmt
+  | AwkNextFileStmt
+  | AwkExitStmt
+  | AwkReturnStmt
+  | AwkDeleteStmt
+  | AwkBlock;
+
+export interface AwkExpressionStmt {
+  type: "expr_stmt";
+  expression: AwkExpr;
+}
+
+export interface AwkPrintStmt {
+  type: "print";
+  args: AwkExpr[];
+  output?: { redirect: ">" | ">>"; file: AwkExpr };
+}
+
+export interface AwkPrintfStmt {
+  type: "printf";
+  format: AwkExpr;
+  args: AwkExpr[];
+  output?: { redirect: ">" | ">>"; file: AwkExpr };
+}
+
+export interface AwkIfStmt {
+  type: "if";
+  condition: AwkExpr;
+  consequent: AwkStmt;
+  alternate?: AwkStmt;
+}
+
+export interface AwkWhileStmt {
+  type: "while";
+  condition: AwkExpr;
+  body: AwkStmt;
+}
+
+export interface AwkDoWhileStmt {
+  type: "do_while";
+  body: AwkStmt;
+  condition: AwkExpr;
+}
+
+export interface AwkForStmt {
+  type: "for";
+  init?: AwkExpr;
+  condition?: AwkExpr;
+  update?: AwkExpr;
+  body: AwkStmt;
+}
+
+export interface AwkForInStmt {
+  type: "for_in";
+  variable: string;
+  array: string;
+  body: AwkStmt;
+}
+
+export interface AwkBlock {
+  type: "block";
+  statements: AwkStmt[];
+}
+
+export interface AwkBreakStmt {
+  type: "break";
+}
+export interface AwkContinueStmt {
+  type: "continue";
+}
+export interface AwkNextStmt {
+  type: "next";
+}
+export interface AwkNextFileStmt {
+  type: "nextfile";
+}
+export interface AwkExitStmt {
+  type: "exit";
+  code?: AwkExpr;
+}
+export interface AwkReturnStmt {
+  type: "return";
+  value?: AwkExpr;
+}
+export interface AwkDeleteStmt {
+  type: "delete";
+  target: AwkArrayAccess | AwkVariable;
+}
+
+// ─── Program Structure ─────────────────────────────────────
+
+export type AwkPattern =
+  | AwkBeginPattern
+  | AwkEndPattern
+  | AwkExprPattern
+  | AwkRegexPattern
+  | AwkRangePattern;
+
+export interface AwkBeginPattern {
+  type: "begin";
+}
+export interface AwkEndPattern {
+  type: "end";
+}
+export interface AwkExprPattern {
+  type: "expr_pattern";
+  expression: AwkExpr;
+}
+export interface AwkRegexPattern {
+  type: "regex_pattern";
+  pattern: string;
+}
+export interface AwkRangePattern {
+  type: "range";
+  start: AwkPattern;
+  end: AwkPattern;
+}
+
+export interface AwkRule {
+  pattern?: AwkPattern;
+  action: AwkBlock;
+}
+
+export interface AwkFunctionDef {
+  name: string;
+  params: string[];
+  body: AwkBlock;
+}
+
+export interface AwkProgram {
+  functions: AwkFunctionDef[];
+  rules: AwkRule[];
+}