Implement directory scanner (#34)

5 files changed, 184 insertions, 86 deletions

diff --git a/src/context.rs b/src/context.rs
index 035eec90a..63ca28e76 100644
--- a/src/context.rs
+++ b/src/context.rs
@@ -1,6 +1,7 @@
 use clap::ArgMatches;
 use git2::Repository;
 use std::env;
+use std::ffi::OsStr;
 use std::fs;
 use std::path::PathBuf;
 
@@ -56,4 +57,138 @@ impl<'a> Context<'a> {
         }
         dir
     }
+
+    // returns a new ScanDir struct with reference to current dir_files of context
+    // see ScanDir for methods
+    pub fn new_scan_dir(&'a self) -> ScanDir<'a> {
+        ScanDir {
+            dir_files: self.dir_files.as_ref(),
+            files: &[],
+            folders: &[],
+            extensions: &[],
+        }
+    }
+}
+
+// A struct of Criteria which will be used to verify current PathBuf is
+// of X language, criteria can be set via the builder pattern
+pub struct ScanDir<'a> {
+    dir_files: &'a Vec<PathBuf>, // Replace with reference
+    files: &'a [&'a str],
+    folders: &'a [&'a str],
+    extensions: &'a [&'a str],
+}
+
+impl<'a> ScanDir<'a> {
+    pub fn set_files(mut self, files: &'a [&'a str]) -> Self {
+        self.files = files;
+        self
+    }
+
+    pub fn set_extensions(mut self, extensions: &'a [&'a str]) -> Self {
+        self.extensions = extensions;
+        self
+    }
+
+    pub fn set_folders(mut self, folders: &'a [&'a str]) -> Self {
+        self.folders = folders;
+        self
+    }
+
+    /// based on the current Pathbuf check to see
+    /// if any of this criteria match or exist and returning a boolean
+    pub fn scan(&mut self) -> bool {
+        self.dir_files.iter().any(|path| {
+            path_has_name(&path, &self.folders)
+                || path_has_name(&path, &self.files)
+                || has_extension(&path, &self.extensions)
+        })
+    }
+}
+
+/// checks to see if the pathbuf matches a file or folder name
+pub fn path_has_name<'a>(dir_entry: &PathBuf, names: &'a [&'a str]) -> bool {
+    let found_file_or_folder_name = names.into_iter().find(|file_or_folder_name| {
+        dir_entry
+            .file_name()
+            .and_then(OsStr::to_str)
+            .unwrap_or_default()
+            == **file_or_folder_name
+    });
+
+    match found_file_or_folder_name {
+        Some(name) => !name.is_empty(),
+        None => false,
+    }
+}
+
+/// checks if pathbuf matches the extension provided
+pub fn has_extension<'a>(dir_entry: &PathBuf, extensions: &'a [&'a str]) -> bool {
+    let found_ext = extensions.into_iter().find(|ext| {
+        dir_entry
+            .extension()
+            .and_then(OsStr::to_str)
+            .unwrap_or_default()
+            == **ext
+    });
+
+    match found_ext {
+        Some(extension) => !extension.is_empty(),
+        None => false,
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_path_has_name() {
+        let mut buf = PathBuf::from("/");
+        let files = vec!["package.json"];
+
+        assert_eq!(path_has_name(&buf, &files), false);
+
+        buf.set_file_name("some-file.js");
+        assert_eq!(path_has_name(&buf, &files), false);
+
+        buf.set_file_name("package.json");
+        assert_eq!(path_has_name(&buf, &files), true);
+    }
+
+    #[test]
+    fn test_has_extension() {
+        let mut buf = PathBuf::from("/");
+        let extensions = vec!["js"];
+
+        assert_eq!(has_extension(&buf, &extensions), false);
+
+        buf.set_file_name("some-file.rs");
+        assert_eq!(has_extension(&buf, &extensions), false);
+
+        buf.set_file_name("some-file.js");
+        assert_eq!(has_extension(&buf, &extensions), true)
+    }
+
+    #[test]
+    fn test_criteria_scan() {
+        let mut failing_criteria = ScanDir {
+            dir_files: &vec![PathBuf::new()],
+            files: &["package.json"],
+            extensions: &["js"],
+            folders: &["node_modules"],
+        };
+
+        // fails if buffer does not match any criteria
+        assert_eq!(failing_criteria.scan(), false);
+
+        let mut passing_criteria = ScanDir {
+            dir_files: &vec![PathBuf::from("package.json")],
+            files: &["package.json"],
+            extensions: &["js"],
+            folders: &["node_modules"],
+        };
+
+        assert_eq!(passing_criteria.scan(), true);
+    }
 }
diff --git a/src/modules/go.rs b/src/modules/go.rs
index f6b2f2c9a..76728e38a 100644
--- a/src/modules/go.rs
+++ b/src/modules/go.rs
@@ -4,59 +4,44 @@ use std::process::Command;
 
 use super::{Context, Module};
 
-/// Creates a segment with the current Python version
+/// Creates a segment with the current Go version
 ///
-/// Will display the Python version if any of the following criteria are met:
-///     - Current directory contains a `.go` file
+/// Will display the Go version if any of the following criteria are met:
 ///     - Current directory contains a `go.mod` file
 ///     - Current directory contains a `go.sum` file
-///     - Current directory contains a `Godeps` directory
 ///     - Current directory contains a `glide.yaml` file
 ///     - Current directory contains a `Gopkg.yml` file
 ///     - Current directory contains a `Gopkg.lock` file
+///     - Current directory contains a `.go` file
+///     - Current directory contains a `Godeps` directory
 pub fn segment(context: &Context) -> Option<Module> {
-    let is_go_project = context.dir_files.iter().any(has_go_files);
+    let is_go_project = context
+        .new_scan_dir()
+        .set_files(&["go.mod", "go.sum", "glide.yaml", "Gopkg.yml", "Gopkg.lock"])
+        .set_extensions(&["go"])
+        .set_folders(&["Godeps"])
+        .scan();
+
     if !is_go_project {
         return None;
     }
 
-    const GO_CHAR: &str = "🐹 ";
-    let module_color = Color::Cyan.bold();
+    match get_go_version() {
+        Some(go_version) => {
+            const GO_CHAR: &str = "🐹 ";
+            let module_color = Color::Cyan.bold();
 
-    let mut module = Module::new("go");
-    module.set_style(module_color);
+            let mut module = Module::new("go");
+            module.set_style(module_color);
 
-    let go_version = get_go_version()?;
-    let formatted_version = format_go_version(go_version)?;
-    module.new_segment("symbol", GO_CHAR);
-    module.new_segment("version", formatted_version);
+            let formatted_version = format_go_version(go_version)?;
+            module.new_segment("symbol", GO_CHAR);
+            module.new_segment("version", formatted_version);
 
-    Some(module)
-}
-
-fn has_go_files(dir_entry: &PathBuf) -> bool {
-    let is_go_mod =
-        |d: &PathBuf| -> bool { d.is_file() && d.file_name().unwrap_or_default() == "go.mod" };
-    let is_go_sum =
-        |d: &PathBuf| -> bool { d.is_file() && d.file_name().unwrap_or_default() == "go.sum" };
-    let is_godeps =
-        |d: &PathBuf| -> bool { d.is_dir() && d.file_name().unwrap_or_default() == "Godeps" };
-    let is_glide_yaml =
-        |d: &PathBuf| -> bool { d.is_file() && d.file_name().unwrap_or_default() == "glide.yaml" };
-    let is_go_file =
-        |d: &PathBuf| -> bool { d.is_file() && d.extension().unwrap_or_default() == "go" };
-    let is_gopkg_yml =
-        |d: &PathBuf| -> bool { d.is_file() && d.file_name().unwrap_or_default() == "Gopkg.yml" };
-    let is_gopkg_lock =
-        |d: &PathBuf| -> bool { d.is_file() && d.file_name().unwrap_or_default() == "Gopkg.lock" };
-
-    is_go_mod(&dir_entry)
-        || is_go_sum(&dir_entry)
-        || is_godeps(&dir_entry)
-        || is_glide_yaml(&dir_entry)
-        || is_go_file(&dir_entry)
-        || is_gopkg_yml(&dir_entry)
-        || is_gopkg_lock(&dir_entry)
+            Some(module)
+        }
+        None => None,
+    }
 }
 
 fn get_go_version() -> Option<String> {
diff --git a/src/modules/nodejs.rs b/src/modules/nodejs.rs
index 6552c5556..b9736687e 100644
--- a/src/modules/nodejs.rs
+++ b/src/modules/nodejs.rs
@@ -1,5 +1,4 @@
 use ansi_term::Color;
-use std::path::PathBuf;
 use std::process::Command;
 
 use super::{Context, Module};
@@ -11,7 +10,13 @@ use super::{Context, Module};
 ///     - Current directory contains a `package.json` file
 ///     - Current directory contains a `node_modules` directory
 pub fn segment(context: &Context) -> Option<Module> {
-    let is_js_project = context.dir_files.iter().any(has_js_files);
+    let is_js_project = context
+        .new_scan_dir()
+        .set_files(&["package.json"])
+        .set_extensions(&["js"])
+        .set_folders(&["node_modules"])
+        .scan();
+
     if !is_js_project {
         return None;
     }
@@ -34,18 +39,6 @@ pub fn segment(context: &Context) -> Option<Module> {
     }
 }
 
-fn has_js_files(dir_entry: &PathBuf) -> bool {
-    let is_js_file =
-        |d: &PathBuf| -> bool { d.is_file() && d.extension().unwrap_or_default() == "js" };
-    let is_node_modules =
-        |d: &PathBuf| -> bool { d.is_dir() && d.file_name().unwrap_or_default() == "node_modules" };
-    let is_package_json = |d: &PathBuf| -> bool {
-        d.is_file() && d.file_name().unwrap_or_default() == "package.json"
-    };
-
-    is_js_file(&dir_entry) || is_node_modules(&dir_entry) || is_package_json(&dir_entry)
-}
-
 fn get_node_version() -> Option<String> {
     match Command::new("node").arg("--version").output() {
         Ok(output) => Some(String::from_utf8(output.stdout).unwrap()),
diff --git a/src/modules/python.rs b/src/modules/python.rs
index 70625a47c..fdab440e3 100644
--- a/src/modules/python.rs
+++ b/src/modules/python.rs
@@ -1,5 +1,4 @@
 use ansi_term::Color;
-use std::path::PathBuf;
 use std::process::Command;
 
 use super::{Context, Module};
@@ -12,7 +11,17 @@ use super::{Context, Module};
 ///     - Current directory contains a `requirements.txt` file
 ///     - Current directory contains a `pyproject.toml` file
 pub fn segment(context: &Context) -> Option<Module> {
-    let is_py_project = context.dir_files.iter().any(has_py_files);
+    let is_py_project = context
+        .new_scan_dir()
+        .set_files(&[
+            "requirements.txt",
+            ".python-version",
+            "pyproject.toml",
+            "pyproject.toml",
+        ])
+        .set_extensions(&["py"])
+        .scan();
+
     if !is_py_project {
         return None;
     }
@@ -35,25 +44,6 @@ pub fn segment(context: &Context) -> Option<Module> {
     }
 }
 
-fn has_py_files(dir_entry: &PathBuf) -> bool {
-    let is_py_file =
-        |d: &PathBuf| -> bool { d.is_file() && d.extension().unwrap_or_default() == "py" };
-    let is_python_version = |d: &PathBuf| -> bool {
-        d.is_file() && d.file_name().unwrap_or_default() == ".python-version"
-    };
-    let is_requirements_txt = |d: &PathBuf| -> bool {
-        d.is_file() && d.file_name().unwrap_or_default() == "requirements.txt"
-    };
-    let is_py_project = |d: &PathBuf| -> bool {
-        d.is_file() && d.file_name().unwrap_or_default() == "pyproject.toml"
-    };
-
-    is_py_file(&dir_entry)
-        || is_python_version(&dir_entry)
-        || is_requirements_txt(&dir_entry)
-        || is_py_project(&dir_entry)
-}
-
 fn get_python_version() -> Option<String> {
     match Command::new("python").arg("--version").output() {
         Ok(output) => Some(String::from_utf8(output.stdout).unwrap()),
diff --git a/src/modules/rust.rs b/src/modules/rust.rs
index 1f0ae6036..ab3679e76 100644
--- a/src/modules/rust.rs
+++ b/src/modules/rust.rs
@@ -1,5 +1,4 @@
 use ansi_term::Color;
-use std::path::PathBuf;
 use std::process::Command;
 
 use super::{Context, Module};
@@ -7,10 +6,15 @@ use super::{Context, Module};
 /// Creates a segment with the current Rust version
 ///
 /// Will display the Rust version if any of the following criteria are met:
-///     - Current directory contains a `.rs` file
+///     - Current directory contains a file with a `.rs` extension
 ///     - Current directory contains a `Cargo.toml` file
 pub fn segment(context: &Context) -> Option<Module> {
-    let is_rs_project = context.dir_files.iter().any(has_rs_files);
+    let is_rs_project = context
+        .new_scan_dir()
+        .set_files(&["Cargo.toml"])
+        .set_extensions(&["rs"])
+        .scan();
+
     if !is_rs_project {
         return None;
     }
@@ -33,15 +37,6 @@ pub fn segment(context: &Context) -> Option<Module> {
     }
 }
 
-fn has_rs_files(dir_entry: &PathBuf) -> bool {
-    let is_rs_file =
-        |d: &PathBuf| -> bool { d.is_file() && d.extension().unwrap_or_default() == "rs" };
-    let is_cargo_toml =
-        |d: &PathBuf| -> bool { d.is_file() && d.file_name().unwrap_or_default() == "Cargo.toml" };
-
-    is_rs_file(&dir_entry) || is_cargo_toml(&dir_entry)
-}
-
 fn get_rust_version() -> Option<String> {
     match Command::new("rustc").arg("-V").output() {
         Ok(output) => Some(String::from_utf8(output.stdout).unwrap()),