Add export manager and CSV export capability

src/hyperfine/export/mod.rs

@@ -0,0 +1,96 @@
+mod csv;
+
+use self::csv::CsvExporter;
+
+use std::io::Result;
+
+/// The ExportEntry is the main set of values that will
+/// be exported to files when requested.
+#[derive(Debug, Default, Clone, Serialize)]
+pub struct ExportEntry {
+    /// The command that was run
+    command: String,
+    /// The mean run time
+    mean: f64,
+    /// The standard deviation of all run times
+    stddev: f64,
+    /// Time spend in user space
+    user: f64,
+    /// Time spent in system space
+    system: f64,
+}
+
+impl ExportEntry {
+    /// Create a new ExportEntry with the given values
+    pub fn new(command: String, mean: f64, stddev: f64, user: f64, system: f64) -> Self {
+        ExportEntry {
+            command,
+            mean,
+            stddev,
+            user,
+            system,
+        }
+    }
+}
+
+/// The ResultExportType enum is used to denote the desired form
+/// of exporter to use for a given file.
+pub enum ResultExportType {
+    /// Export to a csv file with the provided name
+    Csv(String),
+}
+
+/// A ResultExporter is responsible for writing all results to the
+/// appropriate file
+pub trait ResultExporter {
+    /// Add an additional entry to the exporter for writing
+    fn add_entry(&mut self, entry: ExportEntry);
+    /// Write all entries to the target destination
+    fn write(&self) -> Result<()>;
+}
+
+/// The ExportManager handles coordination of multiple ResultExporters
+pub trait ExportManager {
+    /// Add a new exporter to this manager for the given type
+    fn add_exporter(&mut self, for_type: &ResultExportType);
+
+    /// Add a new result to all exporters contained in the manager
+    fn add_result(&mut self, result: ExportEntry);
+
+    /// Trigger writes from all exporters
+    fn write_results(&self) -> Result<()>;
+}
+
+/// Create a new ExportManager
+pub fn create_export_manager() -> Box<ExportManager> {
+    Box::new(Exporter {
+        exporters: Vec::new(),
+    })
+}
+
+/// The Exporter is the internal implementation of the ExportManager
+struct Exporter {
+    exporters: Vec<Box<ResultExporter>>,
+}
+
+impl ExportManager for Exporter {
+    fn add_exporter(&mut self, for_type: &ResultExportType) {
+        match for_type {
+            &ResultExportType::Csv(ref file_name) => self.exporters
+                .push(Box::from(CsvExporter::new(file_name.clone()))),
+        };
+    }
+
+    fn add_result(&mut self, result: ExportEntry) {
+        for exp in self.exporters.iter_mut() {
+            exp.add_entry(result.clone());
+        }
+    }
+
+    fn write_results(&self) -> Result<()> {
+        for exp in &self.exporters {
+            exp.write()?;
+        }
+        Ok(())
+    }
+}