gui: spec-blind suite; search finds the best match, axis ticks never overflow

tests/spec_gui.rs (31 spec-blind tests): exact money text round-trips,
file names never escape the folder or hit a Windows device name, history
against a browser model, fuzzy search against a subsequence model, axis
ticks, the view model against ledger-core, and the attention list.

Found and fixed:
- fuzzy matched greedily, so "ac c" scored 1 for "c" (the "c" inside
  "ac") instead of 5 for the word "c"; it now scores the best alignment.
- ticks accumulated float error (a last tick at -5.55e-17 for a top of
  0), gave more than n + 2 ticks at large magnitudes with tiny spans,
  and overflowed for spans near f64's limit. Ticks are now whole
  multiples of the step, checked, with [lo, hi] when f64 has no nice step.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX

crates/ledger-gui/Cargo.toml

@@ -31,6 +31,7 @@ serde_json = "1"
 [dev-dependencies]
 chrono = "0.4"
 egui_kittest = { version = "0.36", features = ["wgpu", "snapshot", "eframe"] }
+proptest = "1"
 
 [lints]
 workspace = true

crates/ledger-gui/src/charts.rs

@@ -17,30 +17,51 @@ fn f(d: Decimal) -> f64 {
 
 /// ```text
 /// INVARIANTS (finite lo <= hi, n >= 1):
-///   1. Evenly spaced by a step of 1, 2, 2.5, or 5 times a power of ten.
+///   1. Evenly spaced by a step of 1, 2, 2.5, or 5 times a power of ten
+///      (each tick a whole multiple of the step), all finite.
 ///   2. The first tick is at or below lo and the last at or above hi, so
 ///      no data falls outside the gridlines.
 ///   3. At most n + 2 ticks.
+///   When no such step exists in f64 (nice ticks past f64's range, within
+///   a factor of ten of it, or a span too small for the magnitude), the
+///   ticks are just [lo, hi] (or [lo]).
 /// ```
 /// "Nice" axis ticks covering [lo, hi].
-fn ticks(lo: f64, hi: f64, n: usize) -> Vec<f64> {
-    let span = (hi - lo).max(1e-9);
-    let raw = span / n as f64;
-    let mag = 10f64.powf(raw.log10().floor());
-    let step = [1.0, 2.0, 2.5, 5.0, 10.0]
-        .iter()
-        .map(|m| m * mag)
-        .find(|s| span / s <= n as f64)
-        .unwrap_or(10.0 * mag);
-    let start = (lo / step).floor() * step;
-    let mut v = vec![start];
-    // Up to the first tick at or above the top, so the data never pokes
-    // past the last gridline.
-    while *v.last().expect("non-empty") < hi - step * 1e-9 {
-        let next = v.last().expect("non-empty") + step;
-        v.push(next);
+pub fn ticks(lo: f64, hi: f64, n: usize) -> Vec<f64> {
+    let n = n.max(1);
+    let fallback = || if lo == hi { vec![lo] } else { vec![lo, hi] };
+    let span = (hi - lo).max(f64::MIN_POSITIVE);
+    if !span.is_finite() {
+        return fallback();
     }
-    v
+    let raw = span / n as f64;
+    let mut mag = 10f64.powf(raw.log10().floor());
+    // Try the nice steps from the smallest that fits n, coarser as needed
+    // (rounding at large magnitudes can cost a tick).
+    for _ in 0..4 {
+        for m in [1.0, 2.0, 2.5, 5.0] {
+            let step = m * mag;
+            if !step.is_finite() || step <= 0.0 || span / step > n as f64 {
+                continue;
+            }
+            let (k0, k1) = ((lo / step).floor(), (hi / step).ceil());
+            if !(k0.is_finite() && k1.is_finite()) || k1 - k0 + 1.0 > (n + 2) as f64 {
+                continue;
+            }
+            let v: Vec<f64> = (0..=(k1 - k0) as i64)
+                .map(|k| (k0 + k as f64) * step)
+                .collect();
+            let ok = v.iter().all(|x| x.is_finite())
+                && v.windows(2).all(|w| w[1] > w[0])
+                && v.first().is_some_and(|f| *f <= lo)
+                && v.last().is_some_and(|l| *l >= hi);
+            if ok {
+                return v;
+            }
+        }
+        mag *= 10.0;
+    }
+    fallback()
 }
 
 fn money_label(v: f64) -> String {

crates/ledger-gui/src/lib.rs

@@ -4,16 +4,16 @@
 #![allow(missing_docs)]
 
 pub mod app;
-mod attention;
+pub mod attention;
 pub mod books;
-mod charts;
+pub mod charts;
 pub mod data;
 pub mod demo;
-mod export;
-mod fmt;
+pub mod export;
+pub mod fmt;
 pub mod nav;
 pub mod pages;
-mod palette;
+pub mod palette;
 mod receipts;
 mod theme;
 mod widgets;

crates/ledger-gui/src/palette.rs

@@ -157,42 +157,58 @@ impl Palette {
 ///      query matches everything with score 0.
 ///   2. A match's score is at least the number of non-space query
 ///      characters; consecutive matches and matches at a word start score
-///      more, so a word-start prefix scores at least as high as any
-///      other match of the same query.
+///      more. The score is the best over every way to match (not the
+///      first match found), so a hay holding the query whole at a word
+///      start scores at least as high as any hay's match of it.
 /// ```
-fn fuzzy(hay: &str, query: &str) -> Option<i32> {
-    if query.is_empty() {
+pub fn fuzzy(hay: &str, query: &str) -> Option<i32> {
+    let hay: Vec<char> = hay.to_lowercase().chars().collect();
+    // Query characters, each marked whether a space came just before it
+    // (a space ends a run: the next match earns no run bonus).
+    let mut q: Vec<(char, bool)> = Vec::new();
+    let mut after_space = false;
+    for c in query.to_lowercase().chars() {
+        if c == ' ' {
+            after_space = true;
+        } else {
+            q.push((c, after_space));
+            after_space = false;
+        }
+    }
+    if q.is_empty() {
         return Some(0);
     }
-    let hay: Vec<char> = hay.to_lowercase().chars().collect();
-    let mut score = 0;
-    let mut hi = 0;
-    let mut prev_match = false;
-    for qc in query.to_lowercase().chars() {
-        if qc == ' ' {
-            prev_match = false;
-            continue;
-        }
-        let mut found = false;
-        while hi < hay.len() {
-            let c = hay[hi];
-            hi += 1;
-            if c == qc {
-                score += if prev_match { 6 } else { 1 };
-                if hi == 1 || !hay[hi - 2].is_alphanumeric() {
-                    score += 4;
-                }
-                prev_match = true;
-                found = true;
-                break;
+    // The best score over every way to match (a greedy left-most match
+    // can miss a word start further on): best[j] is the top score for the
+    // query so far with its last character at hay[j].
+    let word_start = |j: usize| j == 0 || !hay[j - 1].is_alphanumeric();
+    let mut best: Vec<Option<i32>> = hay
+        .iter()
+        .enumerate()
+        .map(|(j, &c)| (c == q[0].0).then(|| 1 + if word_start(j) { 4 } else { 0 }))
+        .collect();
+    for &(qc, gap) in &q[1..] {
+        let mut next = vec![None; hay.len()];
+        // The best score ending strictly before j.
+        let mut before: Option<i32> = None;
+        for j in 0..hay.len() {
+            if hay[j] == qc {
+                let bonus = if word_start(j) { 4 } else { 0 };
+                let run = if gap {
+                    None
+                } else {
+                    j.checked_sub(1)
+                        .and_then(|p| best[p])
+                        .map(|s| s + 6 + bonus)
+                };
+                let jump = before.map(|s| s + 1 + bonus);
+                next[j] = run.max(jump);
             }
-            prev_match = false;
-        }
-        if !found {
-            return None;
+            before = before.max(best[j]);
         }
+        best = next;
     }
-    Some(score)
+    best.into_iter().flatten().max()
 }
 
 fn search(b: &Books, query: &str) -> Vec<Item> {

crates/ledger-gui/tests/spec_gui.proptest-regressions

@@ -0,0 +1,12 @@
+# Seeds for failure cases proptest has generated in the past. It is
+# automatically read and these particular cases re-run before any
+# novel cases are generated.
+#
+# It is recommended to check this file in to source control so that
+# everyone who runs the test benefits from these saved cases.
+cc e1abb99e086123434884a3986a83c6a04e095d9f4a0d6b0b8f9490c3ef7a3fb4 # shrinks to center = 721350534.2385265, span_exp = -2, n = 1
+cc 67ed971061efe8d67c42fac1e63e6d1943358315b8d447482fd8e723d2850577 # shrinks to query = "c", head = "ac", tail = "", other = "c"
+cc 2f8bab974c3fe9cadfdc5f457bec479125025199050e9ad7d2a868750951e1d8 # shrinks to a = 0.0, b = -0.4626437454001001, n = 3, same = false
+cc a358fb90f0d14b99605d509ebbe00e178285158223ab165a54676d70a1a01287 # shrinks to plan = BooksPlan { threshold: "0.00", entries: [EntryPlan { day: 0, debits: [(0, 1)], credit_accounts: [0], split_pct: 1, scale: 3, post: false, receipt: false }], reverse: None }
+cc 3b788cd1184019b4cf33c3150a5368e446d20bdc52afe98b6d3094516ac7e5ac # shrinks to a = 1.2726536570066655e-11, b = -0.44869856490793697, n = 1, same = false
+cc adafa1178ead699437f63287c9be531c043a0a9de3ee34f908e4ca3ef81bc6c3 # shrinks to center = 79655376.47358137, span_exp = -6, n = 5