refact: Use Option instead of custom ValueTypeOrThunk

This loses the custom name for "thunk", but checking thunkness is
a niche use case that I don't think we should spend much code on.

(cherry picked from commit 7bdff525c13234ce6a32ea9346292d948b0840c1)
This commit is contained in:
Robert Hensing 2024-06-14 18:42:23 +02:00
parent 19361acb12
commit 22ffd20c53
2 changed files with 44 additions and 43 deletions

View file

@ -1,4 +1,4 @@
use crate::value::{Int, Value, ValueType, ValueTypeOrThunk}; use crate::value::{Int, Value, ValueType};
use anyhow::Context as _; use anyhow::Context as _;
use anyhow::{bail, Result}; use anyhow::{bail, Result};
use lazy_static::lazy_static; use lazy_static::lazy_static;
@ -133,20 +133,20 @@ impl EvalState {
} }
self.context.check_err() self.context.check_err()
} }
pub fn value_type_unforced(&self, value: &Value) -> ValueTypeOrThunk { pub fn value_type_unforced(&self, value: &Value) -> Option<ValueType> {
let r = unsafe { raw::get_type(self.context.ptr(), value.raw_ptr()) }; let r = unsafe { raw::get_type(self.context.ptr(), value.raw_ptr()) };
self.context.check_err().unwrap(); self.context.check_err().unwrap();
ValueTypeOrThunk::from_raw(r) ValueType::from_raw(r)
} }
pub fn value_type(&self, value: &Value) -> Result<ValueType> { pub fn value_type(&self, value: &Value) -> Result<ValueType> {
match self.value_type_unforced(value) { match self.value_type_unforced(value) {
ValueTypeOrThunk::ValueType(a) => Ok(a), Some(a) => Ok(a),
ValueTypeOrThunk::Thunk => { None => {
self.force(value)?; self.force(value)?;
match self.value_type_unforced(value) { match self.value_type_unforced(value) {
ValueTypeOrThunk::ValueType(a) => Ok(a), Some(a) => Ok(a),
ValueTypeOrThunk::Thunk => { None => {
panic!("values should not be thunks after having been forced.") panic!("Nix value must not be thunk after being forced.")
} }
} }
} }
@ -488,9 +488,9 @@ mod tests {
let v2 = v.clone(); let v2 = v.clone();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::Int)); assert!(t == Some(ValueType::Int));
let t2 = es.value_type_unforced(&v2); let t2 = es.value_type_unforced(&v2);
assert!(t2 == ValueTypeOrThunk::ValueType(ValueType::Int)); assert!(t2 == Some(ValueType::Int));
gc_now(); gc_now();
}) })
.unwrap(); .unwrap();
@ -504,7 +504,7 @@ mod tests {
let v = es.eval_from_string("true", "<test>").unwrap(); let v = es.eval_from_string("true", "<test>").unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::Bool)); assert!(t == Some(ValueType::Bool));
}) })
.unwrap(); .unwrap();
} }
@ -532,7 +532,7 @@ mod tests {
let v = es.eval_from_string("{ }", "<test>").unwrap(); let v = es.eval_from_string("{ }", "<test>").unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::AttrSet)); assert!(t == Some(ValueType::AttrSet));
let attrs = es.require_attrs_names(&v).unwrap(); let attrs = es.require_attrs_names(&v).unwrap();
assert_eq!(attrs.len(), 0); assert_eq!(attrs.len(), 0);
}) })
@ -653,7 +653,7 @@ mod tests {
let v = es.eval_from_string("\"hello\"", "<test>").unwrap(); let v = es.eval_from_string("\"hello\"", "<test>").unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::String)); assert!(t == Some(ValueType::String));
let s = es.require_string(&v).unwrap(); let s = es.require_string(&v).unwrap();
assert!(s == "hello"); assert!(s == "hello");
}) })
@ -705,7 +705,7 @@ mod tests {
.unwrap(); .unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::String)); assert!(t == Some(ValueType::String));
let r = es.require_string(&v); let r = es.require_string(&v);
assert!(r.is_err()); assert!(r.is_err());
assert!(r assert!(r
@ -726,7 +726,7 @@ mod tests {
.unwrap(); .unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::String)); assert!(t == Some(ValueType::String));
// TODO // TODO
// let r = es.require_string_without_context(&v); // let r = es.require_string_without_context(&v);
// assert!(r.is_err()); // assert!(r.is_err());
@ -743,7 +743,7 @@ mod tests {
let v = es.new_value_str("hello").unwrap(); let v = es.new_value_str("hello").unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::String)); assert!(t == Some(ValueType::String));
let s = es.require_string(&v).unwrap(); let s = es.require_string(&v).unwrap();
assert!(s == "hello"); assert!(s == "hello");
}) })
@ -758,7 +758,7 @@ mod tests {
let v = es.new_value_str("").unwrap(); let v = es.new_value_str("").unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::String)); assert!(t == Some(ValueType::String));
let s = es.require_string(&v).unwrap(); let s = es.require_string(&v).unwrap();
assert!(s == ""); assert!(s == "");
}) })
@ -792,7 +792,7 @@ mod tests {
let v = es.new_value_int(42).unwrap(); let v = es.new_value_int(42).unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::Int)); assert!(t == Some(ValueType::Int));
let i = es.require_int(&v).unwrap(); let i = es.require_int(&v).unwrap();
assert!(i == 42); assert!(i == 42);
}) })
@ -807,7 +807,7 @@ mod tests {
let v = es.eval_from_string("{ }", "<test>").unwrap(); let v = es.eval_from_string("{ }", "<test>").unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::AttrSet)); assert!(t == Some(ValueType::AttrSet));
}) })
.unwrap(); .unwrap();
} }
@ -822,7 +822,7 @@ mod tests {
.unwrap(); .unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::List)); assert!(t == Some(ValueType::List));
}) })
.unwrap(); .unwrap();
} }
@ -884,7 +884,7 @@ mod tests {
let v = es.call(f, a).unwrap(); let v = es.call(f, a).unwrap();
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::Int)); assert!(t == Some(ValueType::Int));
let i = es.require_int(&v).unwrap(); let i = es.require_int(&v).unwrap();
assert!(i == 3); assert!(i == 3);
}) })
@ -900,10 +900,10 @@ mod tests {
let f = es.eval_from_string("x: x + 1", "<test>").unwrap(); let f = es.eval_from_string("x: x + 1", "<test>").unwrap();
let a = es.eval_from_string("2", "<test>").unwrap(); let a = es.eval_from_string("2", "<test>").unwrap();
let v = es.new_value_apply(&f, &a).unwrap(); let v = es.new_value_apply(&f, &a).unwrap();
assert!(es.value_type_unforced(&v) == ValueTypeOrThunk::Thunk); assert!(es.value_type_unforced(&v) == None);
es.force(&v).unwrap(); es.force(&v).unwrap();
let t = es.value_type_unforced(&v); let t = es.value_type_unforced(&v);
assert!(t == ValueTypeOrThunk::ValueType(ValueType::Int)); assert!(t == Some(ValueType::Int));
let i = es.require_int(&v).unwrap(); let i = es.require_int(&v).unwrap();
assert!(i == 3); assert!(i == 3);
}) })

View file

@ -22,28 +22,29 @@ pub enum ValueType {
Unknown, Unknown,
} }
#[derive(Eq, PartialEq, Debug)] impl ValueType {
pub enum ValueTypeOrThunk { /// Convert a raw value type to a `ValueType`.
ValueType(ValueType), ///
Thunk, /// Return `None` if the Value is still a thunk (i.e. not yet evaluated).
} ///
/// Return `Some(ValueType::Unknown)` if the value type is not recognized.
impl ValueTypeOrThunk { pub(crate) fn from_raw(raw: raw::ValueType) -> Option<ValueType> {
pub(crate) fn from_raw(raw: raw::ValueType) -> ValueTypeOrThunk {
match raw { match raw {
raw::ValueType_NIX_TYPE_ATTRS => ValueTypeOrThunk::ValueType(ValueType::AttrSet), raw::ValueType_NIX_TYPE_ATTRS => Some(ValueType::AttrSet),
raw::ValueType_NIX_TYPE_BOOL => ValueTypeOrThunk::ValueType(ValueType::Bool), raw::ValueType_NIX_TYPE_BOOL => Some(ValueType::Bool),
raw::ValueType_NIX_TYPE_EXTERNAL => ValueTypeOrThunk::ValueType(ValueType::External), raw::ValueType_NIX_TYPE_EXTERNAL => Some(ValueType::External),
raw::ValueType_NIX_TYPE_FLOAT => ValueTypeOrThunk::ValueType(ValueType::Float), raw::ValueType_NIX_TYPE_FLOAT => Some(ValueType::Float),
raw::ValueType_NIX_TYPE_FUNCTION => ValueTypeOrThunk::ValueType(ValueType::Function), raw::ValueType_NIX_TYPE_FUNCTION => Some(ValueType::Function),
raw::ValueType_NIX_TYPE_INT => ValueTypeOrThunk::ValueType(ValueType::Int), raw::ValueType_NIX_TYPE_INT => Some(ValueType::Int),
raw::ValueType_NIX_TYPE_LIST => ValueTypeOrThunk::ValueType(ValueType::List), raw::ValueType_NIX_TYPE_LIST => Some(ValueType::List),
raw::ValueType_NIX_TYPE_NULL => ValueTypeOrThunk::ValueType(ValueType::Null), raw::ValueType_NIX_TYPE_NULL => Some(ValueType::Null),
raw::ValueType_NIX_TYPE_PATH => ValueTypeOrThunk::ValueType(ValueType::Path), raw::ValueType_NIX_TYPE_PATH => Some(ValueType::Path),
raw::ValueType_NIX_TYPE_STRING => ValueTypeOrThunk::ValueType(ValueType::String), raw::ValueType_NIX_TYPE_STRING => Some(ValueType::String),
raw::ValueType_NIX_TYPE_THUNK => ValueTypeOrThunk::Thunk,
raw::ValueType_NIX_TYPE_THUNK => None,
// This would happen if a new type of value is added in Nix. // This would happen if a new type of value is added in Nix.
_ => ValueTypeOrThunk::ValueType(ValueType::Unknown), _ => Some(ValueType::Unknown),
} }
} }
} }