From 8c4d7e6de3c00ceb5dad8c2e6f7d4940c4f57407 Mon Sep 17 00:00:00 2001
From: Emil Lerch <emil@lerch.org>
Date: Tue, 19 May 2026 13:44:37 -0700
Subject: [PATCH] avoid output under test

---
 src/analytics/projections.zig | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/src/analytics/projections.zig b/src/analytics/projections.zig
index af7cb34..5b3296b 100644
--- a/src/analytics/projections.zig
+++ b/src/analytics/projections.zig
@@ -10,11 +10,24 @@
 ///   - Success rate for a given spending level
 ///   - Percentile bands of portfolio value at each year (for charting)
 const std = @import("std");
+const builtin = @import("builtin");
 const log = std.log.scoped(.projections);
 const shiller = @import("../data/shiller.zig");
 const srf = @import("srf");
 const Date = @import("../Date.zig");
 
+/// `log.warn` wrapper that no-ops under `zig build test`. Used for
+/// validation warnings emitted while parsing user-supplied
+/// `projections.srf` records: the test suite intentionally feeds
+/// invalid inputs to `validRetirementTarget` and the config-loader
+/// to verify they're rejected, but the resulting stderr noise
+/// pollutes test output. Keep using `log.warn` directly when the
+/// warning is interesting in tests too.
+fn warnUser(comptime fmt: []const u8, args: anytype) void {
+    if (builtin.is_test) return;
+    log.warn(fmt, args);
+}
+
 // ── Life events ─────────────────────────────────────────────────
 
 /// A resolved event ready for the simulation loop. All age-based timing
@@ -522,7 +535,7 @@ pub fn parseProjectionsConfig(data: ?[]const u8) UserConfig {
                     if (amt >= 0) {
                         config.annual_contribution = amt;
                     } else {
-                        log.warn("projections: annual_contribution must be >= 0 (got {d}); ignoring record", .{amt});
+                        warnUser("projections: annual_contribution must be >= 0 (got {d}); ignoring record", .{amt});
                     }
                 }
                 if (c.contribution_inflation_adjusted) |b| {
@@ -532,7 +545,7 @@ pub fn parseProjectionsConfig(data: ?[]const u8) UserConfig {
                     if (amt >= 0) {
                         config.target_spending = amt;
                     } else {
-                        log.warn("projections: target_spending must be >= 0 (got {d}); ignoring record", .{amt});
+                        warnUser("projections: target_spending must be >= 0 (got {d}); ignoring record", .{amt});
                     }
                 }
                 if (c.target_spending_inflation_adjusted) |b| {
@@ -580,7 +593,7 @@ pub fn parseProjectionsConfig(data: ?[]const u8) UserConfig {
     // fall back to the default rule. Logged as a warning so the
     // user knows their override was ignored.
     if (annotation_count > 1) {
-        log.warn("projections: retirement_target set on multiple horizons; ignoring all annotations and using default promotion rule", .{});
+        warnUser("projections: retirement_target set on multiple horizons; ignoring all annotations and using default promotion rule", .{});
         config.horizon_targets = @splat(0);
         config.horizon_age_targets = @splat(0);
     }
@@ -596,7 +609,7 @@ pub fn parseProjectionsConfig(data: ?[]const u8) UserConfig {
 fn validRetirementTarget(raw: ?u8) ?u8 {
     const v = raw orelse return null;
     if (v == 90 or v == 95 or v == 99) return v;
-    log.warn("projections: retirement_target must be 90, 95, or 99 (got {d}); annotation ignored", .{v});
+    warnUser("projections: retirement_target must be 90, 95, or 99 (got {d}); annotation ignored", .{v});
     return null;
 }