Implement parser for arithmetic expressions like a++

crates/deno_task_shell/src/grammar.pest

@@ -203,11 +203,18 @@ logical_and = { "&&" }
 logical_or = { "||" }
 
 unary_arithmetic_expr = !{
-    (unary_arithmetic_op | post_arithmetic_op) ~ (parentheses_expr | VARIABLE | NUMBER) |
+    unary_pre_arithmetic_expr | unary_post_arithmetic_expr
+}
+
+unary_pre_arithmetic_expr = !{
+    (post_arithmetic_op | pre_arithmetic_op) ~ (parentheses_expr | VARIABLE | NUMBER)
+}
+
+unary_post_arithmetic_expr = !{
     (parentheses_expr | VARIABLE | NUMBER) ~ post_arithmetic_op
 }
 
-unary_arithmetic_op = _{
+pre_arithmetic_op= _{
     unary_plus | unary_minus | logical_not | bitwise_not
 }
 

crates/deno_task_shell/src/parser.rs

@@ -427,15 +427,10 @@ pub enum ArithmeticPart {
     right: Box<ArithmeticPart>,
   },
   #[error("Invalid unary arithmetic expression")]
-  UnaryArithmeticExpr {
+  UnaryAritheticExpr {
     operator: UnaryArithmeticOp,
     operand: Box<ArithmeticPart>,
   },
-  #[error("Invalid post arithmetic expression")]
-  PostArithmeticExpr {
-    operand: Box<ArithmeticPart>,
-    operator: PostArithmeticOp,
-  },
   #[error("Invalid variable")]
   Variable(String),
   #[error("Invalid number")]
@@ -481,7 +476,9 @@ pub enum AssignmentOp {
 #[cfg_attr(feature = "serialization", derive(serde::Serialize))]
 #[cfg_attr(feature = "serialization", serde(rename_all = "camelCase"))]
 #[derive(Debug, Clone, PartialEq, Eq, Copy)]
-pub enum UnaryArithmeticOp {
+pub enum PreArithmeticOp {
+  Increment,  // ++
+  Decrement,  // --
   Plus,       // +
   Minus,      // -
   LogicalNot, // !
@@ -490,12 +487,20 @@ pub enum UnaryArithmeticOp {
 
 #[cfg_attr(feature = "serialization", derive(serde::Serialize))]
 #[cfg_attr(feature = "serialization", serde(rename_all = "camelCase"))]
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq, Eq, Copy)]
 pub enum PostArithmeticOp {
   Increment, // ++
   Decrement, // --
 }
 
+#[cfg_attr(feature = "serialization", derive(serde::Serialize))]
+#[cfg_attr(feature = "serialization", serde(rename_all = "camelCase"))]
+#[derive(Debug, Clone, PartialEq, Eq, Copy)]
+pub enum UnaryArithmeticOp {
+  Pre(PreArithmeticOp),
+  Post(PostArithmeticOp),
+}
+
 #[cfg_attr(feature = "serialization", derive(serde::Serialize))]
 #[cfg_attr(
   feature = "serialization",
@@ -1419,56 +1424,123 @@ fn parse_arithmetic_expr(pair: Pair<Rule>) -> Result<ArithmeticPart> {
 
 fn parse_unary_arithmetic_expr(pair: Pair<Rule>) -> Result<ArithmeticPart> {
   let mut inner = pair.into_inner();
-  let first = inner.next().unwrap();
+  let first = inner
+    .next()
+    .ok_or_else(|| miette!("Expected unary operator"))?;
 
   match first.as_rule() {
-    Rule::unary_arithmetic_op => {
-      let op = parse_unary_arithmetic_op(first)?;
-      let operand = parse_arithmetic_expr(inner.next().unwrap())?;
-      Ok(ArithmeticPart::UnaryArithmeticExpr {
-        operator: op,
-        operand: Box::new(operand),
-      })
+    Rule::unary_pre_arithmetic_expr => unary_pre_arithmetic_expr(first),
+    Rule::unary_post_arithmetic_expr => unary_post_arithmetic_expr(first),
+    _ => Err(miette!(
+      "Unexpected rule in unary arithmetic expression: {:?}",
+      first.as_rule()
+    )),
+  }
+}
+
+fn unary_pre_arithmetic_expr(pair: Pair<Rule>) -> Result<ArithmeticPart> {
+  let mut inner = pair.into_inner();
+  let first = inner
+    .next()
+    .ok_or_else(|| miette!("Expected unary pre operator"))?;
+  let second = inner.next().ok_or_else(|| miette!("Expected operand"))?;
+  let operand = match second.as_rule() {
+    Rule::parentheses_expr => {
+      let inner = second.into_inner().next().unwrap();
+      let parts = parse_arithmetic_sequence(inner)?;
+      Ok(ArithmeticPart::ParenthesesExpr(Box::new(Arithmetic {
+        parts,
+      })))
     }
-    Rule::post_arithmetic_op => {
-      let operand = parse_arithmetic_expr(inner.next().unwrap())?;
-      let op = parse_post_arithmetic_op(first)?;
-      Ok(ArithmeticPart::PostArithmeticExpr {
+    Rule::VARIABLE => Ok(ArithmeticPart::Variable(second.as_str().to_string())),
+    Rule::NUMBER => Ok(ArithmeticPart::Number(second.as_str().to_string())),
+    _ => Err(miette!(
+      "Unexpected rule in arithmetic expression: {:?}",
+      second.as_rule()
+    )),
+  }?;
+
+  match first.as_rule() {
+    Rule::pre_arithmetic_op => {
+      let op = parse_pre_arithmetic_op(first)?;
+      Ok(ArithmeticPart::UnaryAritheticExpr {
+        operator: UnaryArithmeticOp::Pre(op),
         operand: Box::new(operand),
-        operator: op,
       })
     }
-    _ => {
-      let operand = parse_arithmetic_expr(first)?;
-      let op = parse_post_arithmetic_op(inner.next().unwrap())?;
-      Ok(ArithmeticPart::PostArithmeticExpr {
+    Rule::post_arithmetic_op => {
+      let op = parse_pre_arithmetic_op(first)?;
+      Ok(ArithmeticPart::UnaryAritheticExpr {
+        operator: UnaryArithmeticOp::Pre(op),
         operand: Box::new(operand),
-        operator: op,
       })
     }
+    _ => Err(miette!(
+      "Unexpected rule in unary arithmetic operator: {:?}",
+      first.as_rule()
+    )),
   }
 }
 
-fn parse_unary_arithmetic_op(pair: Pair<Rule>) -> Result<UnaryArithmeticOp> {
-  match pair.as_str() {
-    "+" => Ok(UnaryArithmeticOp::Plus),
-    "-" => Ok(UnaryArithmeticOp::Minus),
-    "!" => Ok(UnaryArithmeticOp::LogicalNot),
-    "~" => Ok(UnaryArithmeticOp::BitwiseNot),
+fn unary_post_arithmetic_expr(pair: Pair<Rule>) -> Result<ArithmeticPart> {
+  let mut inner = pair.into_inner();
+  let first = inner
+    .next()
+    .ok_or_else(|| miette!("Expected unary post operator"))?;
+  let second = inner.next().ok_or_else(|| miette!("Expected operand"))?;
+
+  let operand = match first.as_rule() {
+    Rule::parentheses_expr => {
+      let inner = first.into_inner().next().unwrap();
+      let parts = parse_arithmetic_sequence(inner)?;
+      Ok(ArithmeticPart::ParenthesesExpr(Box::new(Arithmetic {
+        parts,
+      })))
+    }
+    Rule::VARIABLE => Ok(ArithmeticPart::Variable(first.as_str().to_string())),
+    Rule::NUMBER => Ok(ArithmeticPart::Number(first.as_str().to_string())),
+    _ => Err(miette!(
+      "Unexpected rule in arithmetic expression: {:?}",
+      first.as_rule()
+    )),
+  }?;
+  let op = parse_post_arithmetic_op(second)?;
+  Ok(ArithmeticPart::UnaryAritheticExpr {
+    operator: UnaryArithmeticOp::Post(op),
+    operand: Box::new(operand),
+  })
+}
+
+fn parse_pre_arithmetic_op(pair: Pair<Rule>) -> Result<PreArithmeticOp> {
+  let first = pair
+    .into_inner()
+    .next()
+    .ok_or_else(|| miette!("Expected increment or decrement operator"))?;
+  match first.as_rule() {
+    Rule::increment => Ok(PreArithmeticOp::Increment),
+    Rule::decrement => Ok(PreArithmeticOp::Decrement),
+    Rule::add => Ok(PreArithmeticOp::Plus),
+    Rule::subtract => Ok(PreArithmeticOp::Minus),
+    Rule::logical_not => Ok(PreArithmeticOp::LogicalNot),
+    Rule::bitwise_not => Ok(PreArithmeticOp::BitwiseNot),
     _ => Err(miette!(
-      "Invalid unary arithmetic operator: {}",
-      pair.as_str()
+      "Unexpected rule in post arithmetic operator: {:?}",
+      first.as_rule()
     )),
   }
 }
 
 fn parse_post_arithmetic_op(pair: Pair<Rule>) -> Result<PostArithmeticOp> {
-  match pair.as_str() {
-    "++" => Ok(PostArithmeticOp::Increment),
-    "--" => Ok(PostArithmeticOp::Decrement),
+  let first = pair
+    .into_inner()
+    .next()
+    .ok_or_else(|| miette!("Expected increment or decrement operator"))?;
+  match first.as_rule() {
+    Rule::increment => Ok(PostArithmeticOp::Increment),
+    Rule::decrement => Ok(PostArithmeticOp::Decrement),
     _ => Err(miette!(
-      "Invalid post arithmetic operator: {}",
-      pair.as_str()
+      "Unexpected rule in post arithmetic operator: {:?}",
+      first.as_rule()
     )),
   }
 }

crates/deno_task_shell/src/shell/execute.rs

@@ -13,47 +13,23 @@ use thiserror::Error;
 use tokio::task::JoinHandle;
 use tokio_util::sync::CancellationToken;
 
-use crate::parser::AssignmentOp;
-use crate::parser::BinaryOp;
-use crate::parser::Condition;
-use crate::parser::ConditionInner;
-use crate::parser::ElsePart;
-use crate::parser::IoFile;
-use crate::parser::RedirectOpInput;
-use crate::parser::RedirectOpOutput;
-use crate::parser::UnaryOp;
-use crate::shell::commands::ShellCommand;
-use crate::shell::commands::ShellCommandContext;
-use crate::shell::types::pipe;
-use crate::shell::types::ArithmeticResult;
-use crate::shell::types::ArithmeticValue;
-use crate::shell::types::EnvChange;
-use crate::shell::types::ExecuteResult;
-use crate::shell::types::FutureExecuteResult;
-use crate::shell::types::ShellPipeReader;
-use crate::shell::types::ShellPipeWriter;
-use crate::shell::types::ShellState;
-
-use crate::parser::Arithmetic;
-use crate::parser::ArithmeticPart;
-use crate::parser::BinaryArithmeticOp;
-use crate::parser::Command;
-use crate::parser::CommandInner;
-use crate::parser::IfClause;
-use crate::parser::PipeSequence;
-use crate::parser::PipeSequenceOperator;
-use crate::parser::Pipeline;
-use crate::parser::PipelineInner;
-use crate::parser::Redirect;
-use crate::parser::RedirectFd;
-use crate::parser::RedirectOp;
-use crate::parser::Sequence;
-use crate::parser::SequentialList;
-use crate::parser::SimpleCommand;
-use crate::parser::UnaryArithmeticOp;
-use crate::parser::Word;
-use crate::parser::WordPart;
-use crate::shell::types::WordEvalResult;
+use crate::parser::{
+  AssignmentOp, BinaryOp, Condition, ConditionInner, ElsePart, IoFile,
+  RedirectOpInput, RedirectOpOutput, UnaryArithmeticOp, UnaryOp,
+};
+use crate::shell::commands::{ShellCommand, ShellCommandContext};
+use crate::shell::types::{
+  pipe, ArithmeticResult, ArithmeticValue, EnvChange, ExecuteResult,
+  FutureExecuteResult, ShellPipeReader, ShellPipeWriter, ShellState,
+  WordEvalResult,
+};
+
+use crate::parser::{
+  Arithmetic, ArithmeticPart, BinaryArithmeticOp, Command, CommandInner,
+  IfClause, PipeSequence, PipeSequenceOperator, Pipeline, PipelineInner,
+  Redirect, RedirectFd, RedirectOp, Sequence, SequentialList, SimpleCommand,
+  Word, WordPart,
+};
 
 use super::command::execute_unresolved_command_name;
 use super::command::UnresolvedCommandName;
@@ -599,7 +575,10 @@ async fn evaluate_arithmetic_part(
           }?
         }
       };
-      state.apply_env_var(name, &applied_value.to_string());
+      state.apply_change(&EnvChange::SetShellVar(
+        (&name).to_string(),
+        applied_value.value.to_string(),
+      ));
       Ok(
         applied_value
           .clone()
@@ -639,13 +618,9 @@ async fn evaluate_arithmetic_part(
       let rhs = Box::pin(evaluate_arithmetic_part(right, state)).await?;
       apply_conditional_binary_op(lhs, operator, rhs)
     }
-    ArithmeticPart::UnaryArithmeticExpr { operator, operand } => {
+    ArithmeticPart::UnaryAritheticExpr { operator, operand } => {
       let val = Box::pin(evaluate_arithmetic_part(operand, state)).await?;
-      apply_unary_op(*operator, val)
-    }
-    ArithmeticPart::PostArithmeticExpr { operand, .. } => {
-      let val = Box::pin(evaluate_arithmetic_part(operand, state)).await?;
-      Ok(val)
+      apply_unary_op(state, *operator, val, operand)
     }
     ArithmeticPart::Variable(name) => state
       .get_var(name)
@@ -729,19 +704,15 @@ fn apply_conditional_binary_op(
 }
 
 fn apply_unary_op(
+  state: &mut ShellState,
   op: UnaryArithmeticOp,
   val: ArithmeticResult,
+  operand: &ArithmeticPart,
 ) -> Result<ArithmeticResult, Error> {
-  match op {
-    UnaryArithmeticOp::Plus => Ok(val),
-    UnaryArithmeticOp::Minus => val.checked_neg(),
-    UnaryArithmeticOp::LogicalNot => Ok(if val.is_zero() {
-      ArithmeticResult::new(ArithmeticValue::Integer(1))
-    } else {
-      ArithmeticResult::new(ArithmeticValue::Integer(0))
-    }),
-    UnaryArithmeticOp::BitwiseNot => val.checked_not(),
-  }
+  let result = val.unary_op(operand, op)?;
+  let result_clone = result.clone();
+  state.apply_changes(&result_clone.changes);
+  Ok(result)
 }
 
 async fn execute_pipe_sequence(
@@ -1350,6 +1321,7 @@ fn evaluate_word_parts(
       if !current_text.is_empty() {
         result.extend(evaluate_word_text(state, current_text, is_quoted)?);
       }
+      result.with_changes(changes);
       Ok(result)
     }
     .boxed_local()