Default to git diff when stdin is empty

Author: haasonsaas

README.md

@@ -74,6 +74,9 @@ git diff | diffscope review
 # Review a specific file diff
 diffscope review --diff patch.diff
 
+# Run without stdin to review uncommitted changes
+diffscope review
+
 # Get enhanced analysis with smart review
 git diff | diffscope smart-review
 ```
@@ -89,6 +92,9 @@ diffscope git uncommitted
 # Compare your branch to main
 diffscope git branch main
 
+# Compare your branch to the repo default
+diffscope git branch
+
 # Get AI-powered commit message suggestions
 diffscope git suggest
 ```

src/main.rs

@@ -7,6 +7,7 @@ use anyhow::Result;
 use clap::{Parser, Subcommand};
 use once_cell::sync::Lazy;
 use regex::Regex;
+use std::io::IsTerminal;
 use std::path::{Path, PathBuf};
 use tracing::info;
 use tracing_subscriber::EnvFilter;
@@ -230,6 +231,18 @@ async fn review_command(
 
     let diff_content = if let Some(path) = diff_path {
         tokio::fs::read_to_string(path).await?
+    } else if std::io::stdin().is_terminal() {
+        if let Ok(git) = core::GitIntegration::new(".") {
+            let diff = git.get_uncommitted_diff()?;
+            if diff.is_empty() {
+                println!("No changes found");
+                return Ok(());
+            }
+            diff
+        } else {
+            println!("No diff provided and not in a git repository.");
+            return Ok(());
+        }
     } else {
         use std::io::Read;
         let mut buffer = String::new();
@@ -1163,6 +1176,18 @@ async fn smart_review_command(
 
     let diff_content = if let Some(path) = diff_path {
         tokio::fs::read_to_string(path).await?
+    } else if std::io::stdin().is_terminal() {
+        if let Ok(git) = core::GitIntegration::new(".") {
+            let diff = git.get_uncommitted_diff()?;
+            if diff.is_empty() {
+                println!("No changes found");
+                return Ok(());
+            }
+            diff
+        } else {
+            println!("No diff provided and not in a git repository.");
+            return Ok(());
+        }
     } else {
         use std::io::Read;
         let mut buffer = String::new();