diff options
Diffstat (limited to 'nixpkgs/pkgs/test/nixpkgs-check-by-name/src/nix_file.rs')
| -rw-r--r-- | nixpkgs/pkgs/test/nixpkgs-check-by-name/src/nix_file.rs | 555 |
1 files changed, 0 insertions, 555 deletions
diff --git a/nixpkgs/pkgs/test/nixpkgs-check-by-name/src/nix_file.rs b/nixpkgs/pkgs/test/nixpkgs-check-by-name/src/nix_file.rs deleted file mode 100644 index e2dc1e196141..000000000000 --- a/nixpkgs/pkgs/test/nixpkgs-check-by-name/src/nix_file.rs +++ /dev/null @@ -1,555 +0,0 @@ -//! This is a utility module for interacting with the syntax of Nix files - -use crate::utils::LineIndex; -use anyhow::Context; -use itertools::Either::{self, Left, Right}; -use relative_path::RelativePathBuf; -use rnix::ast; -use rnix::ast::Expr; -use rnix::ast::HasEntry; -use rowan::ast::AstNode; -use rowan::TextSize; -use rowan::TokenAtOffset; -use std::collections::hash_map::Entry; -use std::collections::HashMap; -use std::fs::read_to_string; -use std::path::Path; -use std::path::PathBuf; - -/// A structure to store parse results of Nix files in memory, -/// making sure that the same file never has to be parsed twice -#[derive(Default)] -pub struct NixFileStore { - entries: HashMap<PathBuf, NixFile>, -} - -impl NixFileStore { - /// Get the store entry for a Nix file if it exists, otherwise parse the file, insert it into - /// the store, and return the value - /// - /// Note that this function only gives an anyhow::Result::Err for I/O errors. - /// A parse error is anyhow::Result::Ok(Result::Err(error)) - pub fn get(&mut self, path: &Path) -> anyhow::Result<&NixFile> { - match self.entries.entry(path.to_owned()) { - Entry::Occupied(entry) => Ok(entry.into_mut()), - Entry::Vacant(entry) => Ok(entry.insert(NixFile::new(path)?)), - } - } -} - -/// A structure for storing a successfully parsed Nix file -pub struct NixFile { - /// The parent directory of the Nix file, for more convenient error handling - pub parent_dir: PathBuf, - /// The path to the file itself, for errors - pub path: PathBuf, - pub syntax_root: rnix::Root, - pub line_index: LineIndex, -} - -impl NixFile { - /// Creates a new NixFile, failing for I/O or parse errors - fn new(path: impl AsRef<Path>) -> anyhow::Result<NixFile> { - let Some(parent_dir) = path.as_ref().parent() else { - anyhow::bail!("Could not get parent of path {}", path.as_ref().display()) - }; - - let contents = read_to_string(&path) - .with_context(|| format!("Could not read file {}", path.as_ref().display()))?; - let line_index = LineIndex::new(&contents); - - // NOTE: There's now another Nixpkgs CI check to make sure all changed Nix files parse - // correctly, though that uses mainline Nix instead of rnix, so it doesn't give the same - // errors. In the future we should unify these two checks, ideally moving the other CI - // check into this tool as well and checking for both mainline Nix and rnix. - rnix::Root::parse(&contents) - // rnix's ::ok returns Result<_, _> , so no error is thrown away like it would be with - // std::result's ::ok - .ok() - .map(|syntax_root| NixFile { - parent_dir: parent_dir.to_path_buf(), - path: path.as_ref().to_owned(), - syntax_root, - line_index, - }) - .with_context(|| format!("Could not parse file {} with rnix", path.as_ref().display())) - } -} - -/// Information about callPackage arguments -#[derive(Debug, PartialEq)] -pub struct CallPackageArgumentInfo { - /// The relative path of the first argument, or `None` if it's not a path. - pub relative_path: Option<RelativePathBuf>, - /// Whether the second argument is an empty attribute set - pub empty_arg: bool, -} - -impl NixFile { - /// Returns information about callPackage arguments for an attribute at a specific line/column - /// index. - /// If the definition at the given location is not of the form `<attr> = callPackage <arg1> <arg2>;`, - /// `Ok((None, String))` is returned, with `String` being the definition itself. - /// - /// This function only returns `Err` for problems that can't be caused by the Nix contents, - /// but rather problems in this programs code itself. - /// - /// This is meant to be used with the location returned from `builtins.unsafeGetAttrPos`, e.g.: - /// - Create file `default.nix` with contents - /// ```nix - /// self: { - /// foo = self.callPackage ./default.nix { }; - /// } - /// ``` - /// - Evaluate - /// ```nix - /// builtins.unsafeGetAttrPos "foo" (import ./default.nix { }) - /// ``` - /// results in `{ file = ./default.nix; line = 2; column = 3; }` - /// - Get the NixFile for `.file` from a `NixFileStore` - /// - Call this function with `.line`, `.column` and `relative_to` as the (absolute) current directory - /// - /// You'll get back - /// ```rust - /// Ok(( - /// Some(CallPackageArgumentInfo { path = Some("default.nix"), empty_arg: true }), - /// "foo = self.callPackage ./default.nix { };", - /// )) - /// ``` - /// - /// Note that this also returns the same for `pythonPackages.callPackage`. It doesn't make an - /// attempt at distinguishing this. - pub fn call_package_argument_info_at( - &self, - line: usize, - column: usize, - relative_to: &Path, - ) -> anyhow::Result<(Option<CallPackageArgumentInfo>, String)> { - Ok(match self.attrpath_value_at(line, column)? { - Left(definition) => (None, definition), - Right(attrpath_value) => { - let definition = attrpath_value.to_string(); - let attrpath_value = - self.attrpath_value_call_package_argument_info(attrpath_value, relative_to)?; - (attrpath_value, definition) - } - }) - } - - // Internal function mainly to make it independently testable - fn attrpath_value_at( - &self, - line: usize, - column: usize, - ) -> anyhow::Result<Either<String, ast::AttrpathValue>> { - let index = self.line_index.fromlinecolumn(line, column); - - let token_at_offset = self - .syntax_root - .syntax() - .token_at_offset(TextSize::from(index as u32)); - - // The token_at_offset function takes indices to mean a location _between_ characters, - // which in this case is some spacing followed by the attribute name: - // - // foo = 10; - // /\ - // This is the token offset, we get both the (newline + indentation) on the left side, - // and the attribute name on the right side. - let TokenAtOffset::Between(_space, token) = token_at_offset else { - anyhow::bail!("Line {line} column {column} in {} is not the start of a token, but rather {token_at_offset:?}", self.path.display()) - }; - - // token looks like "foo" - let Some(node) = token.parent() else { - anyhow::bail!( - "Token on line {line} column {column} in {} does not have a parent node: {token:?}", - self.path.display() - ) - }; - - if ast::Attr::can_cast(node.kind()) { - // Something like `foo`, `"foo"` or `${"foo"}` - } else if ast::Inherit::can_cast(node.kind()) { - // Something like `inherit <attr>` or `inherit (<source>) <attr>` - // This is the only other way how `builtins.unsafeGetAttrPos` can return - // attribute positions, but we only look for ones like `<attr-path> = <value>`, so - // ignore this - return Ok(Left(node.to_string())); - } else { - // However, anything else is not expected and smells like a bug - anyhow::bail!( - "Node in {} is neither an attribute node nor an inherit node: {node:?}", - self.path.display() - ) - } - - // node looks like "foo" - let Some(attrpath_node) = node.parent() else { - anyhow::bail!( - "Node in {} does not have a parent node: {node:?}", - self.path.display() - ) - }; - - if !ast::Attrpath::can_cast(attrpath_node.kind()) { - // We know that `node` is an attribute, its parent should be an attribute path - anyhow::bail!( - "In {}, attribute parent node is not an attribute path node: {attrpath_node:?}", - self.path.display() - ) - } - - // attrpath_node looks like "foo.bar" - let Some(attrpath_value_node) = attrpath_node.parent() else { - anyhow::bail!( - "Attribute path node in {} does not have a parent node: {attrpath_node:?}", - self.path.display() - ) - }; - - if !ast::AttrpathValue::can_cast(attrpath_value_node.kind()) { - anyhow::bail!( - "Node in {} is not an attribute path value node: {attrpath_value_node:?}", - self.path.display() - ) - } - // attrpath_value_node looks like "foo.bar = 10;" - - // unwrap is fine because we confirmed that we can cast with the above check. - // We could avoid this `unwrap` for a `clone`, since `cast` consumes the argument, - // but we still need it for the error message when the cast fails. - Ok(Right( - ast::AttrpathValue::cast(attrpath_value_node).unwrap(), - )) - } - - // Internal function mainly to make attrpath_value_at independently testable - fn attrpath_value_call_package_argument_info( - &self, - attrpath_value: ast::AttrpathValue, - relative_to: &Path, - ) -> anyhow::Result<Option<CallPackageArgumentInfo>> { - let Some(attrpath) = attrpath_value.attrpath() else { - anyhow::bail!("attrpath value node doesn't have an attrpath: {attrpath_value:?}") - }; - - // At this point we know it's something like `foo...bar = ...` - - if attrpath.attrs().count() > 1 { - // If the attribute path has multiple entries, the left-most entry is an attribute and - // can't be a `callPackage`. - // - // FIXME: `builtins.unsafeGetAttrPos` will return the same position for all attribute - // paths and we can't really know which one it is. We could have a case like - // `foo.bar = callPackage ... { }` and trying to determine if `bar` is a `callPackage`, - // where this is not correct. - // However, this case typically doesn't occur anyways, - // because top-level packages wouldn't be nested under an attribute set. - return Ok(None); - } - let Some(value) = attrpath_value.value() else { - anyhow::bail!("attrpath value node doesn't have a value: {attrpath_value:?}") - }; - - // At this point we know it's something like `foo = ...` - - let Expr::Apply(apply1) = value else { - // Not even a function call, instead something like `foo = null` - return Ok(None); - }; - let Some(function1) = apply1.lambda() else { - anyhow::bail!("apply node doesn't have a lambda: {apply1:?}") - }; - let Some(arg1) = apply1.argument() else { - anyhow::bail!("apply node doesn't have an argument: {apply1:?}") - }; - - // At this point we know it's something like `foo = <fun> <arg>`. - // For a callPackage, `<fun>` would be `callPackage ./file` and `<arg>` would be `{ }` - - let empty_arg = if let Expr::AttrSet(attrset) = arg1 { - // We can only statically determine whether the argument is empty if it's an attribute - // set _expression_, even though other kind of expressions could evaluate to an attribute - // set _value_. But this is what we want anyways - attrset.entries().next().is_none() - } else { - false - }; - - // Because callPackage takes two curried arguments, the first function needs to be a - // function call itself - let Expr::Apply(apply2) = function1 else { - // Not a callPackage, instead something like `foo = import ./foo` - return Ok(None); - }; - let Some(function2) = apply2.lambda() else { - anyhow::bail!("apply node doesn't have a lambda: {apply2:?}") - }; - let Some(arg2) = apply2.argument() else { - anyhow::bail!("apply node doesn't have an argument: {apply2:?}") - }; - - // At this point we know it's something like `foo = <fun2> <arg2> <arg1>`. - // For a callPackage, `<fun2>` would be `callPackage`, `<arg2>` would be `./file` - - // Check that <arg2> is a path expression - let path = if let Expr::Path(actual_path) = arg2 { - // Try to statically resolve the path and turn it into a nixpkgs-relative path - if let ResolvedPath::Within(p) = self.static_resolve_path(actual_path, relative_to) { - Some(p) - } else { - // We can't statically know an existing path inside Nixpkgs used as <arg2> - None - } - } else { - // <arg2> is not a path, but rather e.g. an inline expression - None - }; - - // Check that <fun2> is an identifier, or an attribute path with an identifier at the end - let ident = match function2 { - Expr::Ident(ident) => { - // This means it's something like `foo = callPackage <arg2> <arg1>` - ident - } - Expr::Select(select) => { - // This means it's something like `foo = self.callPackage <arg2> <arg1>`. - // We also end up here for e.g. `pythonPackages.callPackage`, but the - // callPackage-mocking method will take care of not triggering for this case. - - if select.default_expr().is_some() { - // Very odd case, but this would be `foo = self.callPackage or true ./test.nix {} - // (yes this is valid Nix code) - return Ok(None); - } - let Some(attrpath) = select.attrpath() else { - anyhow::bail!("select node doesn't have an attrpath: {select:?}") - }; - let Some(last) = attrpath.attrs().last() else { - // This case shouldn't be possible, it would be `foo = self. ./test.nix {}`, - // which shouldn't parse - anyhow::bail!("select node has an empty attrpath: {select:?}") - }; - if let ast::Attr::Ident(ident) = last { - ident - } else { - // Here it's something like `foo = self."callPackage" /test.nix {}` - // which we're not gonna bother with - return Ok(None); - } - } - // Any other expression we're not gonna treat as callPackage - _ => return Ok(None), - }; - - let Some(token) = ident.ident_token() else { - anyhow::bail!("ident node doesn't have a token: {ident:?}") - }; - - if token.text() == "callPackage" { - Ok(Some(CallPackageArgumentInfo { - relative_path: path, - empty_arg, - })) - } else { - Ok(None) - } - } -} - -/// The result of trying to statically resolve a Nix path expression -pub enum ResolvedPath { - /// Something like `./foo/${bar}/baz`, can't be known statically - Interpolated, - /// Something like `<nixpkgs>`, can't be known statically - SearchPath, - /// Path couldn't be resolved due to an IO error, - /// e.g. if the path doesn't exist or you don't have the right permissions - Unresolvable(std::io::Error), - /// The path is outside the given absolute path - Outside, - /// The path is within the given absolute path. - /// The `RelativePathBuf` is the relative path under the given absolute path. - Within(RelativePathBuf), -} - -impl NixFile { - /// Statically resolves a Nix path expression and checks that it's within an absolute path - /// - /// E.g. for the path expression `./bar.nix` in `./foo.nix` and an absolute path of the - /// current directory, the function returns `ResolvedPath::Within(./bar.nix)` - pub fn static_resolve_path(&self, node: ast::Path, relative_to: &Path) -> ResolvedPath { - if node.parts().count() != 1 { - // If there's more than 1 interpolated part, it's of the form `./foo/${bar}/baz`. - return ResolvedPath::Interpolated; - } - - let text = node.to_string(); - - if text.starts_with('<') { - // A search path like `<nixpkgs>`. There doesn't appear to be better way to detect - // these in rnix - return ResolvedPath::SearchPath; - } - - // Join the file's parent directory and the path expression, then resolve it - // FIXME: Expressions like `../../../../foo/bar/baz/qux` or absolute paths - // may resolve close to the original file, but may have left the relative_to. - // That should be checked more strictly - match self.parent_dir.join(Path::new(&text)).canonicalize() { - Err(resolution_error) => ResolvedPath::Unresolvable(resolution_error), - Ok(resolved) => { - // Check if it's within relative_to - match resolved.strip_prefix(relative_to) { - Err(_prefix_error) => ResolvedPath::Outside, - Ok(suffix) => ResolvedPath::Within( - RelativePathBuf::from_path(suffix).expect("a relative path"), - ), - } - } - } - } -} - -#[cfg(test)] -mod tests { - use super::*; - use crate::tests; - use indoc::indoc; - - #[test] - fn detects_attributes() -> anyhow::Result<()> { - let temp_dir = tests::tempdir()?; - let file = temp_dir.path().join("file.nix"); - let contents = indoc! {r#" - toInherit: { - foo = 1; - "bar" = 2; - ${"baz"} = 3; - "${"qux"}" = 4; - - # A - quux - # B - = - # C - 5 - # D - ; - # E - - /**/quuux/**/=/**/5/**/;/*E*/ - - inherit toInherit; - inherit (toInherit) toInherit; - } - "#}; - - std::fs::write(&file, contents)?; - - let nix_file = NixFile::new(&file)?; - - // These are builtins.unsafeGetAttrPos locations for the attributes - let cases = [ - (2, 3, Right("foo = 1;")), - (3, 3, Right(r#""bar" = 2;"#)), - (4, 3, Right(r#"${"baz"} = 3;"#)), - (5, 3, Right(r#""${"qux"}" = 4;"#)), - (8, 3, Right("quux\n # B\n =\n # C\n 5\n # D\n ;")), - (17, 7, Right("quuux/**/=/**/5/**/;")), - (19, 10, Left("inherit toInherit;")), - (20, 22, Left("inherit (toInherit) toInherit;")), - ]; - - for (line, column, expected_result) in cases { - let actual_result = nix_file - .attrpath_value_at(line, column) - .context(format!("line {line}, column {column}"))? - .map_right(|node| node.to_string()); - let owned_expected_result = expected_result - .map(|x| x.to_string()) - .map_left(|x| x.to_string()); - assert_eq!( - actual_result, owned_expected_result, - "line {line}, column {column}" - ); - } - - Ok(()) - } - - #[test] - fn detects_call_package() -> anyhow::Result<()> { - let temp_dir = tests::tempdir()?; - let file = temp_dir.path().join("file.nix"); - let contents = indoc! {r#" - self: with self; { - a.sub = null; - b = null; - c = import ./file.nix; - d = import ./file.nix { }; - e = pythonPackages.callPackage ./file.nix { }; - f = callPackage ./file.nix { }; - g = callPackage ({ }: { }) { }; - h = callPackage ./file.nix { x = 0; }; - i = callPackage ({ }: { }) (let in { }); - } - "#}; - - std::fs::write(&file, contents)?; - - let nix_file = NixFile::new(&file)?; - - let cases = [ - (2, None), - (3, None), - (4, None), - (5, None), - ( - 6, - Some(CallPackageArgumentInfo { - relative_path: Some(RelativePathBuf::from("file.nix")), - empty_arg: true, - }), - ), - ( - 7, - Some(CallPackageArgumentInfo { - relative_path: Some(RelativePathBuf::from("file.nix")), - empty_arg: true, - }), - ), - ( - 8, - Some(CallPackageArgumentInfo { - relative_path: None, - empty_arg: true, - }), - ), - ( - 9, - Some(CallPackageArgumentInfo { - relative_path: Some(RelativePathBuf::from("file.nix")), - empty_arg: false, - }), - ), - ( - 10, - Some(CallPackageArgumentInfo { - relative_path: None, - empty_arg: false, - }), - ), - ]; - - for (line, expected_result) in cases { - let (actual_result, _definition) = nix_file - .call_package_argument_info_at(line, 3, temp_dir.path()) - .context(format!("line {line}"))?; - assert_eq!(actual_result, expected_result, "line {line}"); - } - - Ok(()) - } -} |