Store datetimes with fixed offset

fixes #376
sharkdp · Feb 23, 2024 · 6f46e2c · 6f46e2c
1 parent b2681ed
commit 6f46e2c
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Showing 3 changed files with 28 additions and 45 deletions.
diff --git a/numbat/src/ffi.rs b/numbat/src/ffi.rs
@@ -2,8 +2,6 @@ use std::collections::HashMap;
 
 use std::sync::OnceLock;
 
-use chrono::Offset;
-
 use crate::currency::ExchangeRatesCache;
 use crate::interpreter::RuntimeError;
 use crate::pretty_print::PrettyPrint;
@@ -834,11 +832,9 @@ fn chr(args: &[Value]) -> Result<Value> {
 
 fn now(args: &[Value]) -> Result<Value> {
     assert!(args.is_empty());
-    let now = chrono::Utc::now();
-
-    let offset = now.with_timezone(&chrono::Local).offset().fix();
+    let now = chrono::Local::now().fixed_offset();
 
-    Ok(Value::DateTime(now, offset))
+    Ok(Value::DateTime(now))
 }
 
 fn datetime(args: &[Value]) -> Result<Value> {
@@ -850,9 +846,7 @@ fn datetime(args: &[Value]) -> Result<Value> {
         .map_err(RuntimeError::DateParsingError)?
         .ok_or(RuntimeError::DateParsingErrorUnknown)?;
 
-    let offset = crate::datetime::local_offset_for_datetime(&output);
-
-    Ok(Value::DateTime(output.into(), offset))
+    Ok(Value::DateTime(output))
 }
 
 fn format_datetime(args: &[Value]) -> Result<Value> {
@@ -901,8 +895,9 @@ fn from_unixtime(args: &[Value]) -> Result<Value> {
 
     let timestamp = args[0].unsafe_as_quantity().unsafe_value().to_f64() as i64;
 
-    let dt = chrono::DateTime::from_timestamp(timestamp, 0).unwrap();
-    let offset = dt.offset().fix();
+    let dt = chrono::DateTime::from_timestamp(timestamp, 0)
+        .unwrap()
+        .fixed_offset();
 
-    Ok(Value::DateTime(dt, offset))
+    Ok(Value::DateTime(dt))
 }
diff --git a/numbat/src/value.rs b/numbat/src/value.rs
@@ -1,3 +1,5 @@
+use chrono::FixedOffset;
+
 use crate::{pretty_print::PrettyPrint, quantity::Quantity};
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -26,7 +28,7 @@ pub enum Value {
     Boolean(bool),
     String(String),
     /// A DateTime with an associated offset used when pretty printing
-    DateTime(chrono::DateTime<chrono::Utc>, chrono::FixedOffset),
+    DateTime(chrono::DateTime<chrono::FixedOffset>),
     FunctionReference(FunctionReference),
 }
 
@@ -59,8 +61,8 @@ impl Value {
     }
 
     #[track_caller]
-    pub fn unsafe_as_datetime(&self) -> &chrono::DateTime<chrono::Utc> {
-        if let Value::DateTime(dt, _) = self {
+    pub fn unsafe_as_datetime(&self) -> &chrono::DateTime<chrono::FixedOffset> {
+        if let Value::DateTime(dt) = self {
             dt
         } else {
             panic!("Expected value to be a string");
@@ -83,7 +85,7 @@ impl std::fmt::Display for Value {
             Value::Quantity(q) => write!(f, "{}", q),
             Value::Boolean(b) => write!(f, "{}", b),
             Value::String(s) => write!(f, "\"{}\"", s),
-            Value::DateTime(dt, _) => write!(f, "datetime(\"{}\")", dt),
+            Value::DateTime(dt) => write!(f, "datetime(\"{}\")", dt),
             Value::FunctionReference(r) => write!(f, "{}", r),
         }
     }
@@ -95,11 +97,7 @@ impl PrettyPrint for Value {
             Value::Quantity(q) => q.pretty_print(),
             Value::Boolean(b) => b.pretty_print(),
             Value::String(s) => s.pretty_print(),
-            Value::DateTime(dt, offset) => {
-                let l: chrono::DateTime<chrono::FixedOffset> =
-                    chrono::DateTime::from_naive_utc_and_offset(dt.naive_utc(), *offset);
-                crate::markup::string(l.to_rfc2822())
-            }
+            Value::DateTime(dt) => crate::markup::string(dt.to_rfc2822()),
             Value::FunctionReference(r) => crate::markup::string(r.to_string()),
         }
     }

diff --git a/numbat/src/vm.rs b/numbat/src/vm.rs
@@ -533,9 +533,9 @@ impl Vm {
     }
 
     #[track_caller]
-    fn pop_datetime(&mut self) -> chrono::DateTime<chrono::Utc> {
+    fn pop_datetime(&mut self) -> chrono::DateTime<chrono::FixedOffset> {
         match self.pop() {
-            Value::DateTime(q, _) => q,
+            Value::DateTime(q) => q,
             _ => panic!("Expected datetime to be on the top of the stack"),
         }
     }
@@ -664,18 +664,15 @@ impl Vm {
                             (seconds_f.fract() * 1_000_000_000f64).round() as i64,
                         );
 
-                    self.push(Value::DateTime(
-                        match op {
-                            Op::AddToDateTime => lhs
-                                .checked_add_signed(duration)
-                                .ok_or(RuntimeError::DateTimeOutOfRange)?,
-                            Op::SubFromDateTime => lhs
-                                .checked_sub_signed(duration)
-                                .ok_or(RuntimeError::DateTimeOutOfRange)?,
-                            _ => unreachable!(),
-                        },
-                        chrono::Local::now().offset().fix(),
-                    ));
+                    self.push(Value::DateTime(match op {
+                        Op::AddToDateTime => lhs
+                            .checked_add_signed(duration)
+                            .ok_or(RuntimeError::DateTimeOutOfRange)?,
+                        Op::SubFromDateTime => lhs
+                            .checked_sub_signed(duration)
+                            .ok_or(RuntimeError::DateTimeOutOfRange)?,
+                        _ => unreachable!(),
+                    }));
                 }
                 Op::DiffDateTime => {
                     let unit = self.pop_quantity();
@@ -852,9 +849,9 @@ impl Vm {
                                 .parse()
                                 .map_err(|_| RuntimeError::UnknownTimezone(tz_name.into()))?;
 
-                            let offset = dt.with_timezone(&tz).offset().fix();
+                            let dt = dt.with_timezone(&tz).fixed_offset();
 
-                            self.push(Value::DateTime(dt, offset));
+                            self.push(Value::DateTime(dt));
                         }
                     }
                 }
@@ -871,14 +868,7 @@ impl Vm {
                             Value::Quantity(q) => q.to_string(),
                             Value::Boolean(b) => b.to_string(),
                             Value::String(s) => s,
-                            Value::DateTime(dt, offset) => {
-                                let l: chrono::DateTime<chrono::FixedOffset> =
-                                    chrono::DateTime::from_naive_utc_and_offset(
-                                        dt.naive_utc(),
-                                        offset,
-                                    );
-                                l.to_rfc2822()
-                            }
+                            Value::DateTime(dt) => dt.to_rfc2822(),
                             Value::FunctionReference(r) => r.to_string(),
                         };
                         joined = part + &joined; // reverse order