Add Lua support to transpiler

Cargo.toml

@@ -6,9 +6,10 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [features]
-default = ["shulkerbox"]
+default = ["lua", "shulkerbox"]
 shulkerbox = ["dep:shulkerbox"]
 serde = ["dep:serde"]
+lua = ["dep:mlua"]
 
 [dependencies]
 chksum-md5 = "0.0.0"
@@ -16,6 +17,7 @@ colored = "2.1.0"
 derive_more = { version = "0.99.17", default-features = false, features = ["deref", "from", "deref_mut"] }
 enum-as-inner = "0.6.0"
 getset = "0.1.2"
+mlua = { version = "0.9.7", features = ["luau"], optional = true }
 serde = { version = "1.0.197", features = ["derive", "rc"], optional = true }
 shulkerbox = { path = "../shulkerbox", optional = true}
 strum = { version = "0.26.2", features = ["derive"] }

grammar.md

@@ -59,36 +59,77 @@ Conditional:
     ;
 ```
 
-### ParenthizedCondition
+### Condition
+```ebnf
+Condition:
+    PrimaryCondition
+    BinaryCondition
+    ;
+```
+
+#### PrimaryCondition
+```ebnf
+PrimaryCondition:
+    ConditionalPrefix
+    | ParenthesizedCondition
+    | StringLiteral
+    ;
+```
+
+#### ConditionalPrefix
+```ebnf
+ConditionalPrefix:
+    ConditionalPrefixOperator PrimaryCondition
+    ;
+```
+
+#### ConditionalPrefixOperator
+``` ebnf
+ConditionalPrefixOperator: '!';
+```
+
+#### BinaryCondition
+``` ebnf
+BinaryCondition:
+    Condition ConditionalBinaryOperator Condition
+    ;
+```
+
+#### ConditionalBinaryOperator
+``` ebnf
+ConditionalBinaryOperator:
+    '&&'
+    | '||'
+    ;
+```
+
+#### ParenthizedCondition
 ```ebnf
 ParenthizedCondition:
     '(' Condition ')'
     ;
 ```
 
-### Condition
-```ebnf
-Condition:
-    StringLiteral
-```
 
 ### Grouping
 ``` ebnf
 Grouping:
     'group' Block
-;
+    ;
 ```
 
 ### Expression
 ```ebnf
 Expression:
     Primary
+    ;
 ```
 
 ### Primary
 ``` ebnf
 Primary:
     FunctionCall
+    ;
 ```
 
 ### FunctionCall
@@ -96,4 +137,11 @@ Primary:
 FunctionCall:
     Identifier '(' (Expression (',' Expression)*)? ')'
     ;
+```
+
+### LuaCode
+```ebnf
+LuaCode:
+    'lua' '(' (Expression (',' Expression)*)? ')' '{' (.*?)* '}'
+    ;
 ```

src/base/source_file.rs

@@ -51,6 +51,12 @@ impl SourceFile {
         &self.content
     }
 
+    /// Get the path of the source file.
+    #[must_use]
+    pub fn path(&self) -> &Path {
+        &self.path
+    }
+
     /// Get the line of the source file at the given line number.
     ///
     /// Numbering starts at 1.
@@ -95,8 +101,6 @@ impl SourceFile {
     #[must_use]
     pub fn get_location(&self, byte_index: usize) -> Option<Location> {
         if self.content.is_char_boundary(byte_index) {
-            None
-        } else {
             // get the line number by binary searching the line ranges
             let line = self
                 .lines
@@ -125,6 +129,8 @@ impl SourceFile {
                 line: line + 1,
                 column,
             })
+        } else {
+            None
         }
     }
 }

src/lexical/token.rs

@@ -23,6 +23,7 @@ pub enum KeywordKind {
     Else,
     Group,
     Run,
+    Lua,
 }
 
 impl ToString for KeywordKind {
@@ -66,6 +67,7 @@ impl KeywordKind {
             Self::Else => "else",
             Self::Group => "group",
             Self::Run => "run",
+            Self::Lua => "lua",
         }
     }
 }

src/lexical/token_stream.rs

@@ -3,8 +3,12 @@
 use std::{fmt::Debug, sync::Arc};
 
 use derive_more::{Deref, From};
+use enum_as_inner::EnumAsInner;
 
-use crate::base::{source_file::SourceFile, Handler};
+use crate::base::{
+    source_file::{SourceElement, SourceFile, Span},
+    Handler,
+};
 
 use super::{
     error::{self, UndelimitedDelimiter},
@@ -164,13 +168,26 @@ impl TokenStream {
 
 /// Is an enumeration of either a [`Token`] or a [`Delimited`].
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
-#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, From)]
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, From, EnumAsInner)]
 #[allow(missing_docs)]
 pub enum TokenTree {
     Token(Token),
     Delimited(Delimited),
 }
 
+impl SourceElement for TokenTree {
+    fn span(&self) -> Span {
+        match self {
+            Self::Token(token) => token.span().to_owned(),
+            Self::Delimited(delimited) => delimited
+                .open
+                .span()
+                .join(&delimited.close.span)
+                .expect("Invalid delimited span"),
+        }
+    }
+}
+
 /// Is an enumeration of the different types of delimiters in the [`Delimited`].
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]

src/syntax/parser.rs

@@ -247,6 +247,12 @@ impl<'a> Frame<'a> {
         self.get_reading(self.token_provider.token_stream().get(self.current_index))
     }
 
+    /// Returns a raw [`Token`] pointing by the `current_index` of the [`Frame`].
+    #[must_use]
+    pub fn peek_raw(&self) -> Option<&TokenTree> {
+        self.token_provider.token_stream().get(self.current_index)
+    }
+
     /// Returns the next significant [`Token`] after the `current_index` of the [`Frame`].
     #[must_use]
     pub fn peek_significant(&self) -> Reading {

src/syntax/syntax_tree/condition.rs

@@ -23,9 +23,9 @@ use crate::{
 /// Syntax Synopsis:
 ///
 /// ``` ebnf
-/// Expression:
+/// PrimaryCondition:
-///     Prefix
+///     ConditionalPrefix
-///     | Parenthesized
+///     | ParenthesizedCondition
 ///     | StringLiteral
 /// ```
 #[allow(missing_docs)]
@@ -88,7 +88,7 @@ impl BinaryCondition {
 /// Syntax Synopsis:
 ///
 /// ``` ebnf
-/// BinaryOperator:
+/// ConditionalBinaryOperator:
 ///     '&&'
 ///     | '||'
 ///     ;
@@ -165,7 +165,7 @@ impl SourceElement for ParenthesizedCondition {
 /// Syntax Synopsis:
 ///
 /// ``` ebnf
-/// PrefixOperator: '!';
+/// ConditionalPrefixOperator: '!';
 /// ```
 #[allow(missing_docs)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
@@ -185,8 +185,8 @@ impl SourceElement for ConditionalPrefixOperator {
 /// Syntax Synopsis:
 ///
 /// ```ebnf
-/// Prefix:
+/// ConditionalPrefix:
-///     ConditionalPrefixOperator StringLiteral
+///     ConditionalPrefixOperator PrimaryCondition
 ///     ;
 /// ```
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
@@ -216,7 +216,10 @@ impl ConditionalPrefix {
 /// Syntax Synopsis:
 ///
 /// ``` ebnf
-/// Condition: PrimaryCondition;
+/// Condition:
+///     PrimaryCondition
+///     | BinaryCondition
+///     ;
 /// ```
 #[allow(missing_docs)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]

src/syntax/syntax_tree/expression.rs

@@ -9,7 +9,7 @@ use crate::{
         Handler,
     },
     lexical::{
-        token::{Identifier, Punctuation, StringLiteral, Token},
+        token::{Identifier, Keyword, KeywordKind, Punctuation, StringLiteral, Token},
         token_stream::Delimiter,
     },
     syntax::{
@@ -47,12 +47,13 @@ impl SourceElement for Expression {
 /// Primary:
 ///     FunctionCall
 /// ```
-#[allow(missing_docs)]
+#[allow(missing_docs, clippy::large_enum_variant)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, EnumAsInner)]
 pub enum Primary {
     FunctionCall(FunctionCall),
     StringLiteral(StringLiteral),
+    Lua(LuaCode),
 }
 
 impl SourceElement for Primary {
@@ -60,6 +61,7 @@ impl SourceElement for Primary {
         match self {
             Self::FunctionCall(function_call) => function_call.span(),
             Self::StringLiteral(string_literal) => string_literal.span(),
+            Self::Lua(lua_code) => lua_code.span(),
         }
     }
 }
@@ -97,6 +99,60 @@ impl SourceElement for FunctionCall {
     }
 }
 
+/// Syntax Synopsis:
+///
+/// ```ebnf
+/// LuaCode:
+///     'lua' '(' (Expression (',' Expression)*)? ')' '{' (.*?)* '}'
+/// ```
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Getters)]
+pub struct LuaCode {
+    /// The `lua` keyword.
+    #[get = "pub"]
+    lua_keyword: Keyword,
+    /// The left parenthesis of the lua code.
+    #[get = "pub"]
+    left_parenthesis: Punctuation,
+    /// The arguments of the lua code.
+    #[get = "pub"]
+    variables: Option<ConnectedList<Identifier, Punctuation>>,
+    /// The right parenthesis of the lua code.
+    #[get = "pub"]
+    right_parenthesis: Punctuation,
+    /// The left brace of the lua code.
+    #[get = "pub"]
+    left_brace: Punctuation,
+    /// The lua code contents.
+    #[get = "pub"]
+    code: String,
+    /// The right brace of the lua code.
+    #[get = "pub"]
+    right_brace: Punctuation,
+}
+
+impl SourceElement for LuaCode {
+    fn span(&self) -> Span {
+        self.lua_keyword
+            .span()
+            .join(&self.right_brace.span)
+            .expect("Invalid lua code span")
+    }
+}
+
+impl LuaCode {
+    /// Dissolves the [`LuaCode`] into its components.
+    #[must_use]
+    pub fn dissolve(self) -> (Keyword, Punctuation, String, Punctuation) {
+        (
+            self.lua_keyword,
+            self.left_brace,
+            self.code,
+            self.right_brace,
+        )
+    }
+}
+
 impl<'a> Parser<'a> {
     /// Parses an [`Expression`]
     pub fn parse_expression(&mut self, handler: &impl Handler<Error>) -> Option<Expression> {
@@ -141,6 +197,65 @@ impl<'a> Parser<'a> {
                 Some(Primary::StringLiteral(literal))
             }
 
+            // lua code expression
+            Reading::Atomic(Token::Keyword(lua_keyword))
+                if lua_keyword.keyword == KeywordKind::Lua =>
+            {
+                // eat the lua keyword
+                self.forward();
+
+                // parse the variable list
+                let variables = self.parse_enclosed_list(
+                    Delimiter::Parenthesis,
+                    ',',
+                    |parser| match parser.next_significant_token() {
+                        Reading::Atomic(Token::Identifier(identifier)) => {
+                            parser.forward();
+                            Some(identifier)
+                        }
+                        _ => None,
+                    },
+                    handler,
+                )?;
+
+                self.stop_at_significant();
+
+                let tree = self.step_into(
+                    Delimiter::Brace,
+                    |parser| {
+                        let first = parser.next_token();
+                        let mut last = parser.next_token();
+
+                        while !parser.is_end() {
+                            last = parser.next_token();
+                        }
+
+                        let combined = first
+                            .into_token()
+                            .and_then(|first| {
+                                first.span().join(&last.into_token().map_or_else(
+                                    || first.span().to_owned(),
+                                    |last| last.span().to_owned(),
+                                ))
+                            })
+                            .expect("Invalid lua code span");
+
+                        Some(combined.str().trim().to_owned())
+                    },
+                    handler,
+                )?;
+
+                Some(Primary::Lua(LuaCode {
+                    lua_keyword,
+                    left_parenthesis: variables.open,
+                    variables: variables.list,
+                    right_parenthesis: variables.close,
+                    left_brace: tree.open,
+                    code: tree.tree?,
+                    right_brace: tree.close,
+                }))
+            }
+
             unexpected => {
                 // make progress
                 self.forward();

src/transpile/error.rs

@@ -10,6 +10,10 @@ pub enum TranspileError {
     MissingFunctionDeclaration(String),
     #[error("Unexpected expression: {}", .0.span().str())]
     UnexpectedExpression(Expression),
+    #[error("Lua code evaluation is disabled.")]
+    LuaDisabled,
+    #[error("Lua runtime error: {}", .0)]
+    LuaRuntimeError(String),
 }
 
 /// The result of a transpilation operation.

src/transpile/lua.rs

@@ -0,0 +1,95 @@
+//! Executes the Lua code and returns the resulting command.
+
+#[cfg(feature = "lua")]
+mod enabled {
+    use mlua::Lua;
+
+    use crate::{
+        base::{source_file::SourceElement, Handler},
+        syntax::syntax_tree::expression::LuaCode,
+        transpile::error::{TranspileError, TranspileResult},
+    };
+
+    impl LuaCode {
+        /// Evaluates the Lua code and returns the resulting command.
+        ///
+        /// # Errors
+        /// - If Lua code evaluation is disabled.
+        pub fn eval_string(
+            &self,
+            handler: &impl Handler<TranspileError>,
+        ) -> TranspileResult<String> {
+            let lua = Lua::new();
+
+            let name = {
+                let span = self.span();
+                let file = span.source_file();
+                let path = file.path();
+
+                let start = span.start_location();
+                let end = span.end_location().unwrap_or_else(|| {
+                    let content_size = file.content().len();
+                    file.get_location(content_size - 1)
+                        .expect("Failed to get location")
+                });
+
+                format!(
+                    "{}:{}:{}-{}:{}",
+                    path.display(),
+                    start.line,
+                    start.column,
+                    end.line,
+                    end.column
+                )
+            };
+
+            let lua_result = lua
+                .load(self.code())
+                .set_name(name)
+                .eval::<String>()
+                .map_err(|err| {
+                    let err = TranspileError::from(err);
+                    handler.receive(err.clone());
+                    err
+                })?;
+
+            Ok(lua_result)
+        }
+    }
+
+    impl From<mlua::Error> for TranspileError {
+        fn from(value: mlua::Error) -> Self {
+            let string = value.to_string();
+            Self::LuaRuntimeError(
+                string
+                    .strip_prefix("runtime error: ")
+                    .unwrap_or(&string)
+                    .to_string(),
+            )
+        }
+    }
+}
+
+#[cfg(not(feature = "lua"))]
+mod disabled {
+    use crate::{
+        base::Handler,
+        syntax::syntax_tree::expression::LuaCode,
+        transpile::error::{TranspileError, TranspileResult},
+    };
+
+    impl LuaCode {
+        /// Will always return an error because Lua code evaluation is disabled.
+        /// Enable the feature `lua` to enable Lua code evaluation.
+        ///
+        /// # Errors
+        /// - If Lua code evaluation is disabled.
+        pub fn eval_string(
+            &self,
+            handler: &impl Handler<TranspileError>,
+        ) -> TranspileResult<String> {
+            handler.receive(TranspileError::LuaDisabled);
+            Err(TranspileError::LuaDisabled)
+        }
+    }
+}

src/transpile/mod.rs

@@ -4,5 +4,7 @@
 #[cfg(feature = "shulkerbox")]
 pub mod conversions;
 pub mod error;
+#[doc(hidden)]
+pub mod lua;
 #[cfg(feature = "shulkerbox")]
 pub mod transpiler;

src/transpile/transpiler.rs

@@ -233,6 +233,9 @@ impl Transpiler {
                 Expression::Primary(Primary::StringLiteral(string)) => {
                     Ok(Some(Command::Raw(string.str_content().to_string())))
                 }
+                Expression::Primary(Primary::Lua(code)) => {
+                    Ok(Some(Command::Raw(code.eval_string(handler)?)))
+                }
             },
             Statement::Block(_) => {
                 unreachable!("Only literal commands are allowed in functions at this time.")