dependencies: switch from `chrono` to `jiff`

We weren't really using `chrono` for anything other than getting the
current time and formatting it for logs.

Unfortunately, this doesn't quite get us to a point where `chrono`
can be removed. From what I can tell, we're still bringing it via
[`tracing-subscriber`](https://docs.rs/tracing-subscriber/latest/tracing_subscriber/)
and
[`quick-junit`](https://docs.rs/quick-junit/latest/quick_junit/).
`tracing-subscriber` does have an
[issue open about Jiff](https://github.com/tokio-rs/tracing/discussions/3128),
but there's no movement on it.

Normally I'd suggest holding off on this since it doesn't get us all of
the way there and it would be better to avoid bringing in two datetime
libraries, but we are, it appears, already there. In particular,
`env_logger` brings in Jiff. So this PR doesn't really make anything
worse, but it does bring us closer to an all-Jiff world.

Cargo.lock

@@ -1558,10 +1558,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d699bc6dfc879fb1bf9bdff0d4c56f0884fc6f0d0eb0fba397a6d00cd9a6b85e"
 dependencies = [
  "jiff-static",
+ "jiff-tzdb-platform",
  "log",
  "portable-atomic",
  "portable-atomic-util",
  "serde",
+ "windows-sys 0.52.0",
 ]
 
 [[package]]
@@ -1575,6 +1577,21 @@ dependencies = [
  "syn 2.0.100",
 ]
 
+[[package]]
+name = "jiff-tzdb"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c1283705eb0a21404d2bfd6eef2a7593d240bc42a0bdb39db0ad6fa2ec026524"
+
+[[package]]
+name = "jiff-tzdb-platform"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "875a5a69ac2bab1a891711cf5eccbec1ce0341ea805560dcd90b7a2e925132e8"
+dependencies = [
+ "jiff-tzdb",
+]
+
 [[package]]
 name = "jobserver"
 version = "0.1.32"
@@ -2476,7 +2493,6 @@ version = "0.0.0"
 dependencies = [
  "anyhow",
  "argfile",
- "chrono",
  "clap",
  "colored 3.0.0",
  "countme",
@@ -2485,6 +2501,7 @@ dependencies = [
  "filetime",
  "insta",
  "insta-cmd",
+ "jiff",
  "rayon",
  "red_knot_project",
  "red_knot_python_semantic",
@@ -2764,7 +2781,6 @@ dependencies = [
  "bincode",
  "bitflags 2.9.0",
  "cachedir",
- "chrono",
  "clap",
  "clap_complete_command",
  "clearscreen",
@@ -2777,6 +2793,7 @@ dependencies = [
  "insta-cmd",
  "is-macro",
  "itertools 0.14.0",
+ "jiff",
  "log",
  "mimalloc",
  "notify",
@@ -2996,7 +3013,6 @@ dependencies = [
  "aho-corasick",
  "anyhow",
  "bitflags 2.9.0",
- "chrono",
  "clap",
  "colored 3.0.0",
  "fern",
@@ -3007,6 +3023,7 @@ dependencies = [
  "is-macro",
  "is-wsl",
  "itertools 0.14.0",
+ "jiff",
  "libcst",
  "log",
  "memchr",

Cargo.toml

@@ -55,7 +55,6 @@ bitflags = { version = "2.5.0" }
 bstr = { version = "1.9.1" }
 cachedir = { version = "0.3.1" }
 camino = { version = "1.1.7" }
-chrono = { version = "0.4.35", default-features = false, features = ["clock"] }
 clap = { version = "4.5.3", features = ["derive"] }
 clap_complete_command = { version = "0.6.0" }
 clearscreen = { version = "4.0.0" }
@@ -95,6 +94,7 @@ insta-cmd = { version = "0.6.0" }
 is-macro = { version = "0.3.5" }
 is-wsl = { version = "0.4.0" }
 itertools = { version = "0.14.0" }
+jiff = { version = "0.2.0" }
 js-sys = { version = "0.3.69" }
 jod-thread = { version = "0.1.2" }
 libc = { version = "0.2.153" }

crates/red_knot/Cargo.toml

@@ -20,12 +20,12 @@ ruff_python_ast = { workspace = true }
 
 anyhow = { workspace = true }
 argfile = { workspace = true }
-chrono = { workspace = true }
 clap = { workspace = true, features = ["wrap_help"] }
 colored = { workspace = true }
 countme = { workspace = true, features = ["enable"] }
 crossbeam = { workspace = true }
 ctrlc = { version = "3.4.4" }
+jiff = { workspace = true }
 rayon = { workspace = true }
 salsa = { workspace = true }
 tracing = { workspace = true, features = ["release_max_level_debug"] }

crates/red_knot/src/logging.rs

@@ -190,8 +190,8 @@ where
         let ansi = writer.has_ansi_escapes();
 
         if self.display_timestamp {
-            let timestamp = chrono::Local::now()
+            let timestamp = jiff::Zoned::now()
-                .format("%Y-%m-%d %H:%M:%S.%f")
+                .strftime("%Y-%m-%d %H:%M:%S.%f")
                 .to_string();
             if ansi {
                 write!(writer, "{} ", timestamp.dimmed())?;
@@ -199,7 +199,7 @@ where
                 write!(
                     writer,
                     "{} ",
-                    chrono::Local::now().format("%Y-%m-%d %H:%M:%S.%f")
+                    jiff::Zoned::now().strftime("%Y-%m-%d %H:%M:%S.%f")
                 )?;
             }
         }

crates/ruff/Cargo.toml

@@ -33,7 +33,6 @@ argfile = { workspace = true }
 bincode = { workspace = true }
 bitflags = { workspace = true }
 cachedir = { workspace = true }
-chrono = { workspace = true }
 clap = { workspace = true, features = ["derive", "env", "wrap_help"] }
 clap_complete_command = { workspace = true }
 clearscreen = { workspace = true }
@@ -43,6 +42,7 @@ globwalk = { workspace = true }
 ignore = { workspace = true }
 is-macro = { workspace = true }
 itertools = { workspace = true }
+jiff = { workspace = true }
 log = { workspace = true }
 notify = { workspace = true }
 path-absolutize = { workspace = true, features = ["once_cell_cache"] }
@@ -75,7 +75,7 @@ test-case = { workspace = true }
 
 [package.metadata.cargo-shear]
 # Used via macro expansion.
-ignored = ["chrono"]
+ignored = ["jiff"]
 
 [target.'cfg(target_os = "windows")'.dependencies]
 mimalloc = { workspace = true }

crates/ruff_linter/Cargo.toml

@@ -32,7 +32,6 @@ ruff_text_size = { workspace = true }
 aho-corasick = { workspace = true }
 anyhow = { workspace = true }
 bitflags = { workspace = true }
-chrono = { workspace = true }
 clap = { workspace = true, features = ["derive", "string"], optional = true }
 colored = { workspace = true }
 fern = { workspace = true }
@@ -43,6 +42,7 @@ is-macro = { workspace = true }
 is-wsl = { workspace = true }
 itertools = { workspace = true }
 libcst = { workspace = true }
+jiff = { workspace = true }
 log = { workspace = true }
 memchr = { workspace = true }
 natord = { workspace = true }

crates/ruff_linter/src/logging.rs

@@ -85,8 +85,8 @@ macro_rules! notify_user {
     ($($arg:tt)*) => {
         println!(
             "[{}] {}",
-            chrono::Local::now()
+            jiff::Zoned::now()
-                .format("%H:%M:%S %p")
+                .strftime("%H:%M:%S %p")
                 .to_string()
                 .dimmed(),
             format_args!($($arg)*)
@@ -142,7 +142,7 @@ pub fn set_up_logging(level: LogLevel) -> Result<()> {
             Level::Info | Level::Debug | Level::Trace => {
                 out.finish(format_args!(
                     "{}[{}][{}] {}",
-                    chrono::Local::now().format("[%Y-%m-%d][%H:%M:%S]"),
+                    jiff::Zoned::now().strftime("[%Y-%m-%d][%H:%M:%S]"),
                     record.target(),
                     record.level(),
                     message