From a87ffb384a04b27fadf84d28949cd19aee793636 Mon Sep 17 00:00:00 2001
From: Rebecca Turner <rbt@sent.as>
Date: Tue, 28 Apr 2026 11:10:44 -0700
Subject: [PATCH] DUX-5101 No "All good" after startup

With `--repl-no-load`, we don't get a compilation summary message ("Ok,
123 modules loaded."), so if everything went well we write... an _empty_
error log, which is not helpful.

Let's synthesize a message in this case: "All good (0 modules)".
---
 src/ghci/compilation_log.rs | 11 +++++++++++
 src/ghci/mod.rs             |  5 +++++
 2 files changed, 16 insertions(+)

diff --git a/src/ghci/compilation_log.rs b/src/ghci/compilation_log.rs
index d05be65d..32d12079 100644
--- a/src/ghci/compilation_log.rs
+++ b/src/ghci/compilation_log.rs
@@ -6,6 +6,8 @@ use crate::ghci::parse::GhcDiagnostic;
 use crate::ghci::parse::GhcMessage;
 use crate::ghci::parse::Severity;
 
+use super::parse::ModulesLoaded;
+
 /// A log of messages from compilation, used to write the error log.
 #[derive(Debug, Clone, Default)]
 pub struct CompilationLog {
@@ -22,6 +24,15 @@ impl CompilationLog {
         Ok(())
     }
 
+    /// If we start up in `--repl-no-load`, we don't get a compilation summary, but we don't want to
+    /// leave the error log empty, so we synthesize an "All good (0 modules)" message.
+    pub fn fill_empty_summary(&mut self) {
+        self.summary.get_or_insert(CompilationSummary {
+            result: CompilationResult::Ok,
+            modules_loaded: ModulesLoaded::Count(0),
+        });
+    }
+
     /// Get the result of compilation.
     pub fn result(&self) -> Option<CompilationResult> {
         self.summary.map(|summary| summary.result)
diff --git a/src/ghci/mod.rs b/src/ghci/mod.rs
index ce74ba86..c520121b 100644
--- a/src/ghci/mod.rs
+++ b/src/ghci/mod.rs
@@ -434,6 +434,11 @@ impl Ghci {
         // Get the initial list of eval commands.
         self.refresh_eval_commands().await?;
 
+        // If we're in `--repl-no-load`, we may not have gotten a summary message. In that case,
+        // fill in an empty "All good (0 modules)" message.
+        //
+        // Note: We ONLY want to do this on startup.
+        log.fill_empty_summary();
         self.finish_compilation(start_instant, log, events).await?;
 
         Ok(())