implement file provider for working without file systems

src/base/error.rs

@@ -1,11 +1,9 @@
-use std::io;
-
 /// An error that occurred during compilation.
 #[allow(missing_docs)]
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
-    #[error("An error occurred while reading the file.")]
-    IoError(#[from] io::Error),
+    #[error("An error occurred while working with Input/Output.")]
+    IoError(String),
     #[error("An error occured while tokenizing the source code.")]
     TokenizeError(#[from] crate::lexical::token::TokenizeError),
     #[error("An error occurred while parsing the source code.")]

src/base/file_provider.rs

@@ -0,0 +1,100 @@
+use std::path::{Path, PathBuf};
+
+use super::Error;
+
+/// A trait for providing file contents.
+pub trait FileProvider {
+    /// Reads the contents of the file at the given path.
+    ///
+    /// # Errors
+    /// - If an error occurs while reading the file.
+    /// - If the file does not exist.
+    fn read_to_string<P: AsRef<Path>>(&self, path: P) -> Result<String, Error>;
+}
+
+/// Provides file contents from the file system.
+#[derive(Debug, Clone)]
+pub struct FsProvider {
+    /// The root directory to base paths off of.
+    root: PathBuf,
+}
+
+impl Default for FsProvider {
+    fn default() -> Self {
+        Self {
+            root: PathBuf::from("."),
+        }
+    }
+}
+
+impl FileProvider for FsProvider {
+    fn read_to_string<P: AsRef<Path>>(&self, path: P) -> Result<String, Error> {
+        let full_path = self.root.join(path);
+        std::fs::read_to_string(full_path).map_err(|err| Error::IoError(err.to_string()))
+    }
+}
+
+#[cfg(feature = "shulkerbox")]
+mod vfs {
+    use super::{Error, FileProvider, Path};
+    use shulkerbox::virtual_fs::{VFile, VFolder};
+
+    impl FileProvider for VFolder {
+        fn read_to_string<P: AsRef<Path>>(&self, path: P) -> Result<String, Error> {
+            normalize_path_str(path).map_or_else(
+                || Err(Error::IoError("Invalid path".to_string())),
+                |path| {
+                    self.get_file(&path)
+                        .ok_or_else(|| Error::IoError("File not found".to_string()))
+                        .and_then(|file| match file {
+                            VFile::Text(text) => Ok(text.to_owned()),
+                            VFile::Binary(bin) => String::from_utf8(bin.clone())
+                                .map_err(|err| Error::IoError(err.to_string())),
+                        })
+                },
+            )
+        }
+    }
+
+    fn normalize_path_str<P: AsRef<Path>>(path: P) -> Option<String> {
+        let mut err = false;
+        let res = path
+            .as_ref()
+            .to_str()?
+            .split('/')
+            .fold(Vec::new(), |mut acc, el| match el {
+                "." | "" => acc,
+                ".." => {
+                    let popped = acc.pop();
+                    if popped.is_none() {
+                        err = true;
+                    }
+                    acc
+                }
+                _ => {
+                    acc.push(el);
+                    acc
+                }
+            })
+            .join("/");
+
+        if err {
+            None
+        } else {
+            Some(res)
+        }
+    }
+
+    #[cfg(test)]
+    mod tests {
+        use super::*;
+
+        #[test]
+        fn test_normalize_path() {
+            assert_eq!(normalize_path_str("a/b/c"), Some("a/b/c".to_string()));
+            assert_eq!(normalize_path_str("a/b/../c"), Some("a/c".to_string()));
+            assert_eq!(normalize_path_str("./a/b/c"), Some("a/b/c".to_string()));
+            assert_eq!(normalize_path_str("../a/b/c"), None);
+        }
+    }
+}

src/base/mod.rs

@@ -9,4 +9,7 @@ pub use error::{Error, Result};
 mod diagnostic;
 pub use diagnostic::{DummyHandler, Handler};
 
+mod file_provider;
+pub use file_provider::{FileProvider, FsProvider};
+
 pub mod log;

src/base/source_file.rs

@@ -3,7 +3,6 @@
 use std::{
     cmp::Ordering,
     fmt::Debug,
-    fs,
     iter::{Iterator, Peekable},
     ops::Range,
     path::{Path, PathBuf},
@@ -13,7 +12,7 @@ use std::{
 
 use getset::{CopyGetters, Getters};
 
-use super::Error;
+use super::{file_provider::FileProvider, Error};
 
 /// Represents a source file that contains the source code.
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
@@ -84,8 +83,8 @@ impl SourceFile {
     ///
     /// # Errors
     /// - [`Error::IoError`]: Error occurred when reading the file contents.
-    pub fn load(path: &Path) -> Result<Arc<Self>, Error> {
-        let source = fs::read_to_string(path).map_err(Error::IoError)?;
+    pub fn load(path: &Path, provider: &impl FileProvider) -> Result<Arc<Self>, Error> {
+        let source = provider.read_to_string(path)?;
         Ok(Self::new(path.to_path_buf(), source))
     }
 

src/lib.rs

@@ -23,7 +23,7 @@ mod public_helpers;
 
 use std::{cell::Cell, fmt::Display, path::Path};
 
-use base::{Handler, Result};
+use base::{FileProvider, Handler, Result};
 use syntax::syntax_tree::program::ProgramFile;
 
 #[cfg(feature = "shulkerbox")]
@@ -31,14 +31,19 @@ use shulkerbox::{datapack::Datapack, virtual_fs::VFolder};
 
 use crate::lexical::token_stream::TokenStream;
 
+const DEFAULT_PACK_FORMAT: u8 = 48;
+
 /// Converts the given source code to tokens.
 ///
 /// # Errors
 /// - If an error occurs while reading the file.
-pub fn tokenize(path: &Path) -> Result<TokenStream> {
+pub fn tokenize<F>(file_provider: &F, path: &Path) -> Result<TokenStream>
+where
+    F: FileProvider,
+{
     let printer = Printer::new();
 
-    public_helpers::tokenize(&printer, path)
+    public_helpers::tokenize(&printer, file_provider, path)
 }
 
 /// Parses the given source code.
@@ -46,10 +51,13 @@ pub fn tokenize(path: &Path) -> Result<TokenStream> {
 /// # Errors
 /// - If an error occurs while reading the file.
 /// - If an error occurs while parsing the source code.
-pub fn parse(path: &Path) -> Result<ProgramFile> {
+pub fn parse<F>(file_provider: &F, path: &Path) -> Result<ProgramFile>
+where
+    F: FileProvider,
+{
     let printer = Printer::new();
 
-    public_helpers::parse(&printer, path)
+    public_helpers::parse(&printer, file_provider, path)
 }
 
 /// Transpiles the given source code into a shulkerbox [`Datapack`].
@@ -62,13 +70,14 @@ pub fn parse(path: &Path) -> Result<ProgramFile> {
 /// - If an error occurs while parsing the source code.
 /// - If an error occurs while transpiling the source code.
 #[cfg(feature = "shulkerbox")]
-pub fn transpile<P>(script_paths: &[(String, P)]) -> Result<Datapack>
+pub fn transpile<F, P>(file_provider: &F, script_paths: &[(String, P)]) -> Result<Datapack>
 where
+    F: FileProvider,
     P: AsRef<Path>,
 {
     let printer = Printer::new();
 
-    public_helpers::transpile(&printer, script_paths)
+    public_helpers::transpile(&printer, file_provider, script_paths)
 }
 
 /// Compiles the given source code.
@@ -81,13 +90,14 @@ where
 /// - If an error occurs while parsing the source code.
 /// - If an error occurs while transpiling the source code.
 #[cfg(feature = "shulkerbox")]
-pub fn compile<P>(script_paths: &[(String, P)]) -> Result<VFolder>
+pub fn compile<F, P>(file_provider: &F, script_paths: &[(String, P)]) -> Result<VFolder>
 where
+    F: FileProvider,
     P: AsRef<Path>,
 {
     let printer = Printer::new();
 
-    public_helpers::compile(&printer, script_paths)
+    public_helpers::compile(&printer, file_provider, script_paths)
 }
 
 struct Printer {

src/public_helpers.rs

@@ -1,7 +1,7 @@
 use std::path::Path;
 
 use crate::{
-    base::{source_file::SourceFile, Error, Result},
+    base::{source_file::SourceFile, Error, FileProvider, Result},
     lexical::token_stream::TokenStream,
     syntax::{parser::Parser, syntax_tree::program::ProgramFile},
     Printer,
@@ -14,17 +14,25 @@ use crate::transpile::transpiler::Transpiler;
 use shulkerbox::{datapack::Datapack, util::compile::CompileOptions, virtual_fs::VFolder};
 
 /// Tokenizes the source code at the given path.
-pub fn tokenize(printer: &Printer, path: &Path) -> Result<TokenStream> {
+pub fn tokenize(
+    printer: &Printer,
+    file_provider: &impl FileProvider,
+    path: &Path,
+) -> Result<TokenStream> {
     tracing::info!("Tokenizing the source code at path: {}", path.display());
 
-    let source_file = SourceFile::load(path)?;
+    let source_file = SourceFile::load(path, file_provider)?;
 
     Ok(TokenStream::tokenize(&source_file, printer))
 }
 
 /// Parses the source code at the given path.
-pub fn parse(printer: &Printer, path: &Path) -> Result<ProgramFile> {
-    let tokens = tokenize(printer, path)?;
+pub fn parse(
+    printer: &Printer,
+    file_provider: &impl FileProvider,
+    path: &Path,
+) -> Result<ProgramFile> {
+    let tokens = tokenize(printer, file_provider, path)?;
 
     if printer.has_printed() {
         return Err(Error::Other(
@@ -50,14 +58,19 @@ pub fn parse(printer: &Printer, path: &Path) -> Result<ProgramFile> {
 
 /// Transpiles the source code at the given paths into a shulkerbox [`Datapack`].
 #[cfg(feature = "shulkerbox")]
-pub fn transpile<P>(printer: &Printer, script_paths: &[(String, P)]) -> Result<Datapack>
+pub fn transpile<F, P>(
+    printer: &Printer,
+    file_provider: &F,
+    script_paths: &[(String, P)],
+) -> Result<Datapack>
 where
+    F: FileProvider,
     P: AsRef<Path>,
 {
     let programs = script_paths
         .iter()
         .map(|(program_identifier, path)| {
-            let program = parse(printer, path.as_ref())?;
+            let program = parse(printer, file_provider, path.as_ref())?;
 
             Ok((program_identifier, program))
         })
@@ -73,7 +86,7 @@ where
 
     tracing::info!("Transpiling the source code.");
 
-    let mut transpiler = Transpiler::new(27);
+    let mut transpiler = Transpiler::new(crate::DEFAULT_PACK_FORMAT);
     transpiler.transpile(&programs, printer)?;
     let datapack = transpiler.into_datapack();
 
@@ -88,11 +101,16 @@ where
 
 /// Compiles the source code at the given paths.
 #[cfg(feature = "shulkerbox")]
-pub fn compile<P>(printer: &Printer, script_paths: &[(String, P)]) -> Result<VFolder>
+pub fn compile<F, P>(
+    printer: &Printer,
+    file_provider: &F,
+    script_paths: &[(String, P)],
+) -> Result<VFolder>
 where
+    F: FileProvider,
     P: AsRef<Path>,
 {
-    let datapack = transpile(printer, script_paths)?;
+    let datapack = transpile(printer, file_provider, script_paths)?;
 
     tracing::info!("Compiling the source code.");