feat: PHP simple assignment

src/codegen/php/expression/assignment.rs

@@ -0,0 +1,38 @@
+use crate::{codegen::Transpilable, php_ast::PhpAssignmentExpression};
+
+impl Transpilable for PhpAssignmentExpression<'_> {
+    fn transpile(&self) -> String {
+        match self {
+            PhpAssignmentExpression::Primary(p) => p.transpile(),
+            PhpAssignmentExpression::SimpleAssignment(assignment) => {
+                let variable_name = &assignment.variable;
+                let expression_str = assignment.assignment.transpile();
+
+                format!("${} = {}", variable_name, expression_str)
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{
+        codegen::Transpilable,
+        php_ast::{PhpAssignmentExpression, PhpPrimaryExpression, PhpSimpleAssignment},
+    };
+
+    #[test]
+    fn should_gen_assignment() {
+        let variable = String::from("name");
+        let value = String::from("John");
+        let assignment = PhpPrimaryExpression::StringLiteral(&value);
+
+        let ast = PhpAssignmentExpression::SimpleAssignment(PhpSimpleAssignment {
+            variable,
+            assignment,
+        });
+        let output = ast.transpile();
+
+        assert_eq!("$name = \"John\"", output)
+    }
+}

src/codegen/php/expression/mod.rs

@@ -1 +1,2 @@
 mod primary_expression;
+mod assignment;

src/codegen/php/expression/primary_expression.rs

@@ -6,6 +6,7 @@ impl Transpilable for PhpPrimaryExpression<'_> {
             PhpPrimaryExpression::IntegerLiteral(value) => value.to_string(),
             PhpPrimaryExpression::FloatingLiteral(value) => value.to_string(),
             PhpPrimaryExpression::StringLiteral(value) => format!("\"{}\"", value),
+            PhpPrimaryExpression::Variable(name) => format!("${}", name),
         }
     }
 }
@@ -58,4 +59,13 @@ mod tests {
 
         assert_eq!("322.644", output)
     }
+
+    #[test]
+    fn should_transpile_variable() {
+        let input = String::from("name");
+        let ast = PhpPrimaryExpression::Variable(&input);
+        let output = ast.transpile();
+
+        assert_eq!("$name", output)
+    }
 }

src/codegen/php/mod.rs

@@ -8,7 +8,7 @@ pub mod statement_list;
 impl Transpilable for PhpExpression<'_> {
     fn transpile(&self) -> String {
         match self {
-            PhpExpression::PrimaryExpression(p) => p.transpile(),
+            PhpExpression::Assignment(p) => p.transpile(),
         }
     }
 }

src/codegen/php/statement/mod.rs

@@ -20,6 +20,10 @@ impl Transpilable for PhpStatement<'_> {
 
                 format!("echo {};", expressions_str)
             }
+            PhpStatement::PhpExpressionStatement(expr) => {
+                let expr_str = expr.transpile();
+                format!("{};", expr_str)
+            }
         }
     }
 }
@@ -28,7 +32,10 @@ impl Transpilable for PhpStatement<'_> {
 mod tests {
     use crate::{
         codegen::Transpilable,
-        php_ast::{PhpExpression, PhpExpressionList, PhpPrimaryExpression, PhpStatement},
+        php_ast::{
+            PhpAssignmentExpression, PhpExpression, PhpExpressionList, PhpPrimaryExpression,
+            PhpStatement,
+        },
     };
 
     #[test]
@@ -47,7 +54,9 @@ mod tests {
         let input = String::from("322");
         let exp_1 = PhpPrimaryExpression::FloatingLiteral(&input);
         let expressions = PhpExpressionList {
-            expressions: vec![PhpExpression::PrimaryExpression(exp_1)],
+            expressions: vec![PhpExpression::Assignment(PhpAssignmentExpression::Primary(
+                exp_1,
+            ))],
         };
         let ast = PhpStatement::PhpEchoStatement(expressions);
         let output = ast.transpile();
@@ -65,8 +74,8 @@ mod tests {
 
         let expressions = PhpExpressionList {
             expressions: vec![
-                PhpExpression::PrimaryExpression(exp_1),
-                PhpExpression::PrimaryExpression(exp_2),
+                PhpExpression::Assignment(PhpAssignmentExpression::Primary(exp_1)),
+                PhpExpression::Assignment(PhpAssignmentExpression::Primary(exp_2)),
             ],
         };
         let ast = PhpStatement::PhpEchoStatement(expressions);
@@ -74,4 +83,16 @@ mod tests {
 
         assert_eq!("echo 322, \"Hai world\";", output)
     }
+
+    #[test]
+    fn should_gen_expression_stmt() {
+        let input = String::from("Hi!");
+        let exp_1 = PhpPrimaryExpression::StringLiteral(&input);
+        let ast = PhpStatement::PhpExpressionStatement(PhpExpression::Assignment(
+            PhpAssignmentExpression::Primary(exp_1),
+        ));
+        let output = ast.transpile();
+
+        assert_eq!("\"Hi!\";", output)
+    }
 }

src/php_ast/mod.rs

@@ -19,6 +19,7 @@ pub struct PhpAst<'a> {
 ///   echo-statement
 pub enum PhpStatement<'a> {
     PhpEchoStatement(PhpExpressionList<'a>),
+    PhpExpressionStatement(PhpExpression<'a>),
 }
 
 pub struct PhpExpressionList<'a> {
@@ -26,15 +27,30 @@ pub struct PhpExpressionList<'a> {
 }
 
 pub enum PhpExpression<'a> {
-    PrimaryExpression(PhpPrimaryExpression<'a>),
+    Assignment(PhpAssignmentExpression<'a>),
+}
+
+pub enum PhpAssignmentExpression<'a> {
+    Primary(PhpPrimaryExpression<'a>),
+    SimpleAssignment(PhpSimpleAssignment<'a>),
+}
+
+pub struct PhpSimpleAssignment<'a> {
+    pub variable: String,
+    pub assignment: PhpPrimaryExpression<'a>,
 }
 
 /// https://phplang.org/spec/19-grammar.html#grammar-primary-expression
 ///
 /// primary-expression:
 ///     literal
+///     variable
 pub enum PhpPrimaryExpression<'a> {
     IntegerLiteral(&'a String),
     FloatingLiteral(&'a String),
     StringLiteral(&'a String),
+    /// https://phplang.org/spec/19-grammar.html#grammar-variable
+    ///
+    /// Supports only variable -> callable-variable -> simple-variable -> variable-name
+    Variable(&'a String),
 }

src/php_ast/transformers/expression.rs

@@ -1,5 +1,8 @@
 use super::super::PhpExpression;
-use crate::{php_ast::PhpPrimaryExpression, syntax::ast::Expression};
+use crate::{
+    php_ast::{PhpAssignmentExpression, PhpPrimaryExpression},
+    syntax::ast::Expression,
+};
 
 use super::PHPTransformable;
 
@@ -11,7 +14,7 @@ impl<'a> PHPTransformable<'a> for Expression<'_> {
         match self {
             Expression::String(value) => {
                 let expr = PhpPrimaryExpression::StringLiteral(value);
-                PhpExpression::PrimaryExpression(expr)
+                PhpExpression::Assignment(PhpAssignmentExpression::Primary(expr))
             }
             _ => todo!("transformation for expression: {:?}", self),
         }

src/php_ast/transformers/module_ast.rs

@@ -1,5 +1,7 @@
 use super::super::PhpAst;
-use crate::php_ast::{PhpExpression, PhpExpressionList, PhpPrimaryExpression, PhpStatement};
+use crate::php_ast::{
+    PhpAssignmentExpression, PhpExpression, PhpExpressionList, PhpPrimaryExpression, PhpStatement,
+};
 use crate::syntax::ast::{Expression, ModuleAST, ModuleMembers};
 
 use super::PHPTransformable;
@@ -34,7 +36,7 @@ impl<'a> PHPTransformable<'a> for ModuleAST<'_> {
                                         match e {
                                             Expression::String(v) => {
                                                 expressions.push(
-                                                    PhpExpression::PrimaryExpression(PhpPrimaryExpression::StringLiteral(v))
+                                                    PhpExpression::Assignment(PhpAssignmentExpression::Primary(PhpPrimaryExpression::StringLiteral(v)))
                                                 )
                                             },
                                             _ => todo!("Non string expressions not supported")