From e96ff7e42d569f5f20d03a968fbc1d1dde9ee0ce Mon Sep 17 00:00:00 2001
From: Ian McLerran <imclerran@protonmail.com>
Date: Mon, 29 Jan 2024 11:43:30 -0600
Subject: [PATCH] Begin migrating Utc and related time components to signed
 integers.

---
 platform/Effect.roc |  2 +-
 platform/Utc.roc    | 14 +++++++-------
 platform/src/lib.rs |  4 ++--
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/platform/Effect.roc b/platform/Effect.roc
index 950ef292..f20b9e9b 100644
--- a/platform/Effect.roc
+++ b/platform/Effect.roc
@@ -88,7 +88,7 @@ tcpWrite : List U8, InternalTcp.Stream -> Effect InternalTcp.WriteResult
 
 pathType : List U8 -> Effect (Result InternalPath.InternalPathType InternalPath.GetMetadataErr)
 
-posixTime : Effect U128
+posixTime : Effect I128
 sleepMillis : U64 -> Effect {}
 
 commandStatus : Box InternalCommand.Command -> Effect (Result {} InternalCommand.CommandErr)
diff --git a/platform/Utc.roc b/platform/Utc.roc
index 297906f3..2ec503f7 100644
--- a/platform/Utc.roc
+++ b/platform/Utc.roc
@@ -12,7 +12,7 @@ interface Utc
     imports [Effect, InternalTask, Task.{ Task }]
 
 ## Stores a timestamp as nanoseconds since UNIX EPOCH
-Utc := U128 implements [Inspect]
+Utc := I128 implements [Inspect]
 
 ## Duration since UNIX EPOCH
 now : Task Utc *
@@ -26,30 +26,30 @@ now =
 nanosPerMilli = 1_000_000
 
 ## Convert Utc timestamp to milliseconds
-toMillisSinceEpoch : Utc -> U128
+toMillisSinceEpoch : Utc -> I128
 toMillisSinceEpoch = \@Utc nanos ->
     nanos // nanosPerMilli
 
 ## Convert milliseconds to Utc timestamp
-fromMillisSinceEpoch : U128 -> Utc
+fromMillisSinceEpoch : I128 -> Utc
 fromMillisSinceEpoch = \millis ->
     @Utc (millis * nanosPerMilli)
 
 ## Convert Utc timestamp to nanoseconds
-toNanosSinceEpoch : Utc -> U128
+toNanosSinceEpoch : Utc -> I128
 toNanosSinceEpoch = \@Utc nanos ->
     nanos
 
 ## Convert nanoseconds to Utc timestamp
-fromNanosSinceEpoch : U128 -> Utc
+fromNanosSinceEpoch : I128 -> Utc
 fromNanosSinceEpoch = @Utc
 
 ## Calculate milliseconds between two Utc timestamps
-deltaAsMillis : Utc, Utc -> U128
+deltaAsMillis : Utc, Utc -> I128
 deltaAsMillis = \@Utc first, @Utc second ->
     (Num.absDiff first second) // nanosPerMilli
 
 ## Calculate nanoseconds between two Utc timestamps
-deltaAsNanos : Utc, Utc -> U128
+deltaAsNanos : Utc, Utc -> I128
 deltaAsNanos = \@Utc first, @Utc second ->
     Num.absDiff first second
diff --git a/platform/src/lib.rs b/platform/src/lib.rs
index a089cc33..a57bebec 100644
--- a/platform/src/lib.rs
+++ b/platform/src/lib.rs
@@ -524,13 +524,13 @@ pub extern "C" fn roc_fx_cwd() -> RocList<u8> {
 }
 
 #[no_mangle]
-pub extern "C" fn roc_fx_posixTime() -> roc_std::U128 {
+pub extern "C" fn roc_fx_posixTime() -> roc_std::I128 {
     // TODO in future may be able to avoid this panic by using C APIs
     let since_epoch = SystemTime::now()
         .duration_since(UNIX_EPOCH)
         .expect("time went backwards");
 
-    roc_std::U128::from(since_epoch.as_nanos())
+    roc_std::I128::from(since_epoch.as_nanos() as i128)
 }
 
 #[no_mangle]