From 2006523ae7b22f4d3ea0fba5f6cbb0625c549fd9 Mon Sep 17 00:00:00 2001
From: "Guillem L. Jara" <4lon3ly0@tutanota.com>
Date: Tue, 26 May 2026 08:01:48 +0200
Subject: [PATCH] interpreter: (in)equality comparisons

---
 interpreter/src/types.rs | 33 ++++++++++++++++++++++++++++++++-
 interpreter/src/vm.rs    | 16 +++++++++-------
 2 files changed, 41 insertions(+), 8 deletions(-)

diff --git a/interpreter/src/types.rs b/interpreter/src/types.rs
index 9243972..38eb4f5 100644
--- a/interpreter/src/types.rs
+++ b/interpreter/src/types.rs
@@ -10,7 +10,7 @@ use std::{
 use ahash::RandomState;
 use hashbrown::HashMap;
 
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone)]
 pub enum Value<'a> {
     Float(f64),
     String(Cow<'a, [u8]>),
@@ -119,6 +119,37 @@ impl<'a> Div for &'_ Value<'a> {
     }
 }
 
+impl PartialEq for Value<'_> {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            // Numeric comparisons
+            (&Self::Float(lhs), &Self::Float(rhs)) => lhs == rhs,
+            (&Self::Bool(lhs), &Self::Bool(rhs)) => lhs == rhs,
+            (&Self::Float(f), &Self::Bool(b)) | (&Self::Bool(b), &Self::Float(f)) => b && f == 1.,
+            // String-based comparisons
+            (Self::String(lhs) | Self::Regex(lhs), Self::String(rhs) | Self::Regex(rhs)) => {
+                lhs == rhs
+            }
+            (&Self::Float(f), Self::String(s) | Self::Regex(s))
+            | (Self::String(s) | Self::Regex(s), &Self::Float(f)) => {
+                f.to_string().as_bytes() == s.as_ref()
+            }
+            (&Self::Bool(b), Self::String(s) | Self::Regex(s))
+            | (Self::String(s) | Self::Regex(s), &Self::Bool(b)) => {
+                (if b { b"1" } else { b"0" }) == s.as_ref()
+            }
+            // True on empty string value.
+            (Self::Untyped | Self::Unassigned, Self::String(s) | Self::Regex(s))
+            | (Self::String(s) | Self::Regex(s), Self::Untyped | Self::Unassigned) => s.is_empty(),
+            (Self::Untyped | Self::Unassigned, Self::Untyped | Self::Unassigned) => true,
+            (Self::Untyped | Self::Unassigned, _) | (_, Self::Untyped | Self::Unassigned) => false,
+            (Self::Array(_), _) | (_, Self::Array(_)) => {
+                panic!("Attempted to use array in scalar context!")
+            }
+        }
+    }
+}
+
 impl Eq for Value<'_> {}
 impl Hash for Value<'_> {
     fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
diff --git a/interpreter/src/vm.rs b/interpreter/src/vm.rs
index ea0059d..b2975d1 100644
--- a/interpreter/src/vm.rs
+++ b/interpreter/src/vm.rs
@@ -12,7 +12,7 @@ use parser::Identifier;
 
 use crate::{
     ir::{
-        NonLocal, OpCode, Reg,
+        Label, NonLocal, OpCode, Reg,
         lower::{Bytecode, Code, ValueContext},
     },
     types::Value,
@@ -127,6 +127,9 @@ impl Interpreter<'_> {
                         OpCode::Subtract => lhs - rhs,
                         OpCode::Multiply => lhs * rhs,
                         OpCode::Divide => lhs / rhs,
+                        // Float values on boolean cmps are intentional.
+                        OpCode::Eq => Value::Float((lhs == rhs) as usize as _),
+                        OpCode::NEq => Value::Float((lhs != rhs) as usize as _),
                         OpCode::Concat => {
                             let mut buf = StdVec::with_capacity(
                                 lhs.string_size_hint() + rhs.string_size_hint(),
@@ -154,18 +157,17 @@ impl Interpreter<'_> {
                     }
                     _ => todo!(),
                 },
-                ix if let Some((cond, true_to, false_to)) = ix.get_branch() => {
+                ix if let Some((cond, Label(true_to), Label(false_to))) = ix.get_branch() => {
                     let label = if self.registers.get(*cond).to_bool() {
-                        true_to.0
+                        *true_to
                     } else {
-                        false_to.0
+                        *false_to
                     };
                     self.program_counter = label as _;
-
                     continue;
                 }
-                ix if let Some(label) = ix.get_jump() => {
-                    self.program_counter = label.0 as _;
+                ix if let Some(&Label(label)) = ix.get_jump() => {
+                    self.program_counter = label as _;
                     continue;
                 }
                 ix => todo!("{ix:?}"),