Files
plainleaf/client/space_lua/ast.ts
T
Matouš Jan FialkaandGitHub e91bec71c0 Fix Lua arithmetic model (#1587)
This patch fixes the Lua arithmetic model at parser level only. Runtime
level fixtures are left for future work.

MOTIVATION

Space Lua treats all numbers as IEEE-754 doubles (JS semantics), so it
preserves negative zero. Lua uses integers and floats. The literal "-0"
in Lua is parsed as unary minus applied to the integer literal "0",
which yields the integer "0" (no sign). This difference flips the sign
of the divisor in "1/-0" and "-1/-0". Although it could be fixed without
touching the parser by changing only unary minus evaluation, this commit
goes a little further and provides integer vs float differenciating at
the parser level as well uses it to fix the unary minus evaluation.

Extensive tests are added to test this exact change works and the Space
Lua arithmetic model is aligned with Lua. Note that things like `-(expr)`
in general may still produce results inconsistent with Lua. This cannot
be fixed at parser level and must be fixed at runtime level which will
need far more complex change to the Space Lua interpreter code. Therefor
these cases we omitted from the tests.

Signed-off-by: Matouš Jan Fialka <mjf@mjf.cz>
2025-10-03 16:31:00 +02:00

307 lines
5.9 KiB
TypeScript

type ASTContext = {
ctx: ASTCtx;
};
export type NumericType = "int" | "float";
export type ASTCtx = {
from?: number;
to?: number;
} & Record<string, any>;
export type LuaBlock = {
type: "Block";
statements: LuaStatement[];
} & ASTContext;
// STATEMENTS
export type LuaReturnStatement = {
type: "Return";
expressions: LuaExpression[];
} & ASTContext;
export type LuaStatement =
| LuaSemicolonStatement
| LuaLabelStatement
| LuaBreakStatement
| LuaGotoStatement
| LuaReturnStatement
| LuaBlock
| LuaWhileStatement
| LuaRepeatStatement
| LuaIfStatement
| LuaForStatement
| LuaForInStatement
| LuaFunctionStatement
| LuaLocalFunctionStatement
| LuaAssignmentStatement
| LuaLocalStatement
| LuaFunctionCallStatement;
export type LuaSemicolonStatement = {
type: "Semicolon";
} & ASTContext;
export type LuaLabelStatement = {
type: "Label";
name: string;
} & ASTContext;
export type LuaBreakStatement = {
type: "Break";
} & ASTContext;
export type LuaGotoStatement = {
type: "Goto";
name: string;
} & ASTContext;
export type LuaWhileStatement = {
type: "While";
condition: LuaExpression;
block: LuaBlock;
} & ASTContext;
export type LuaRepeatStatement = {
type: "Repeat";
block: LuaBlock;
condition: LuaExpression;
} & ASTContext;
export type LuaIfStatement = {
type: "If";
conditions: { condition: LuaExpression; block: LuaBlock }[];
elseBlock?: LuaBlock;
} & ASTContext;
export type LuaForStatement = {
type: "For";
name: string;
start: LuaExpression;
end: LuaExpression;
step?: LuaExpression;
block: LuaBlock;
} & ASTContext;
export type LuaForInStatement = {
type: "ForIn";
names: string[];
expressions: LuaExpression[];
block: LuaBlock;
} & ASTContext;
export type LuaFunctionStatement = {
type: "Function";
name: LuaFunctionName;
body: LuaFunctionBody;
} & ASTContext;
export type LuaLocalFunctionStatement = {
type: "LocalFunction";
name: string;
body: LuaFunctionBody;
} & ASTContext;
export type LuaFunctionName = {
type: "FunctionName";
propNames: string[];
colonName?: string;
} & ASTContext;
export type LuaFunctionBody = {
type: "FunctionBody";
parameters: string[];
block: LuaBlock;
} & ASTContext;
export type LuaAssignmentStatement = {
type: "Assignment";
variables: LuaLValue[];
expressions: LuaExpression[];
} & ASTContext;
export type LuaLValue =
| LuaVariable
| LuaPropertyAccessExpression
| LuaTableAccessExpression;
export type LuaLocalStatement = {
type: "Local";
names: LuaAttName[];
expressions?: LuaExpression[];
} & ASTContext;
export type LuaAttName = {
type: "AttName";
name: string;
attribute?: string;
} & ASTContext;
export type LuaFunctionCallStatement = {
type: "FunctionCallStatement";
call: LuaFunctionCallExpression;
} & ASTContext;
// EXPRESSIONS
export type LuaExpression =
| LuaNilLiteral
| LuaBooleanLiteral
| LuaNumberLiteral
| LuaStringLiteral
| LuaPrefixExpression
| LuaBinaryExpression
| LuaUnaryExpression
| LuaTableConstructor
| LuaFunctionDefinition
| LuaQueryExpression;
export type LuaNilLiteral = {
type: "Nil";
} & ASTContext;
export type LuaBooleanLiteral = {
type: "Boolean";
value: boolean;
} & ASTContext;
export type LuaNumberLiteral = {
type: "Number";
value: number;
numericType: NumericType;
} & ASTContext;
export type LuaStringLiteral = {
type: "String";
value: string;
} & ASTContext;
export type LuaPrefixExpression =
| LuaVariableExpression
| LuaParenthesizedExpression
| LuaFunctionCallExpression;
export type LuaParenthesizedExpression = {
type: "Parenthesized";
expression: LuaExpression;
} & ASTContext;
export type LuaVariableExpression =
| LuaVariable
| LuaPropertyAccessExpression
| LuaTableAccessExpression;
export type LuaVariable = {
type: "Variable";
name: string;
} & ASTContext;
export type LuaPropertyAccessExpression = {
type: "PropertyAccess";
object: LuaPrefixExpression;
property: string;
} & ASTContext;
export type LuaTableAccessExpression = {
type: "TableAccess";
object: LuaPrefixExpression;
key: LuaExpression;
} & ASTContext;
export type LuaFunctionCallExpression = {
type: "FunctionCall";
prefix: LuaPrefixExpression;
name?: string;
args: LuaExpression[];
} & ASTContext;
export type LuaBinaryExpression = {
type: "Binary";
operator: string;
left: LuaExpression;
right: LuaExpression;
} & ASTContext;
export type LuaUnaryExpression = {
type: "Unary";
operator: string;
argument: LuaExpression;
} & ASTContext;
export type LuaTableConstructor = {
type: "TableConstructor";
fields: LuaTableField[];
} & ASTContext;
export type LuaTableField =
| LuaDynamicField
| LuaPropField
| LuaExpressionField;
export type LuaDynamicField = {
type: "DynamicField";
key: LuaExpression;
value: LuaExpression;
} & ASTContext;
export type LuaPropField = {
type: "PropField";
key: string;
value: LuaExpression;
} & ASTContext;
export type LuaExpressionField = {
type: "ExpressionField";
value: LuaExpression;
} & ASTContext;
export type LuaFunctionDefinition = {
type: "FunctionDefinition";
body: LuaFunctionBody;
} & ASTContext;
// Query stuff
export type LuaQueryExpression = {
type: "Query";
clauses: LuaQueryClause[];
} & ASTContext;
export type LuaQueryClause =
| LuaFromClause
| LuaWhereClause
| LuaLimitClause
| LuaOrderByClause
| LuaSelectClause;
export type LuaFromClause = {
type: "From";
name?: string;
expression: LuaExpression;
} & ASTContext;
export type LuaWhereClause = {
type: "Where";
expression: LuaExpression;
} & ASTContext;
export type LuaLimitClause = {
type: "Limit";
limit: LuaExpression;
offset?: LuaExpression;
} & ASTContext;
export type LuaOrderByClause = {
type: "OrderBy";
orderBy: LuaOrderBy[];
} & ASTContext;
export type LuaOrderBy = {
type: "Order";
expression: LuaExpression;
direction: "asc" | "desc";
} & ASTContext;
export type LuaSelectClause = {
type: "Select";
expression: LuaExpression;
} & ASTContext;