Fix issue 205 and add prakriya tests

tbdasap · tbdasap · commit e4d0f7a6f2fd · 2026-01-26T22:43:31.000+05:30
diff --git a/vidyut-prakriya/src/angasya/abhyasasya.rs b/vidyut-prakriya/src/angasya/abhyasasya.rs
@@ -249,23 +249,59 @@ fn try_general_rules(p: &mut Prakriya, i: usize) -> Option<()> {
         p.run_at("7.4.68", i, op::text("viT"));
     }
 
-    let abhyasa = p.get(i)?;
-    if abhyasa.has_adi(SHAR) && abhyasa.has_at(1, KHAY) {
-        let abhyasa = &mut p.get_mut(i)?;
-        let res = try_shar_purva(&abhyasa.text);
-        if res != abhyasa.text {
-            abhyasa.text = res;
-            p.step("7.4.61");
+    let mut abhyasa_has_changed = true;
+    let mut current_abhyasa_text;
+
+    // The transformations prescribed in abhyasa angakarya
+    // seem to be designed to converge on repetition. This may be the
+    // vivakshA
+    while abhyasa_has_changed {
+        let abhyasa = p.get(i)?;
+        current_abhyasa_text = abhyasa.text.clone();
+
+        if abhyasa.has_adi(SHAR) && abhyasa.has_at(1, KHAY) {
+            let abhyasa = p.get_mut(i)?;
+            let res = try_shar_purva(&abhyasa.text);
+            if res != abhyasa.text {
+                abhyasa.text = res;
+                p.step("7.4.61");
+            }
+        } else {
+            let abhyasa = p.get_mut(i)?;
+            let res = try_haladi(&abhyasa.text);
+            if res != abhyasa.text {
+                abhyasa.text = res;
+                p.step("7.4.60");
+            }
         }
-    } else {
-        let abhyasa = &mut p.get_mut(i)?;
-        let res = try_haladi(&abhyasa.text);
-        if res != abhyasa.text {
-            abhyasa.text = res;
-            p.step("7.4.60");
+
+        if p.has(i, |t| t.has_antya('f') || t.has_antya('F')) {
+            p.run_at("7.4.66", i, op::antya("a"));
+            p.run_at("1.1.51", i, op::antya("ar"));
+        }
+
+        // no-hrasva is for pA --> apIpyat.
+        let abhyasa = p.get(i)?;
+        if al::is_dirgha(abhyasa.antya()?) && !abhyasa.has_tag(T::FlagNoHrasva) {
+            let val = al::to_hrasva(abhyasa.antya()?)?;
+            p.run_at("7.4.59", i, op::antya_char(&val));
+        }
+
+        let dhatu = p.get(i_dhatu)?;
+        let last = p.terms().last()?;
+        if dhatu.has_u("i\\R") && last.has_tag(T::kit) && last.has_lakara(Lit) {
+            // IyatuH, IyuH
+            p.run_at("7.4.69", i, op::adi("I"));
+        }
+
+        let abhyasa = p.get_mut(i)?;
+        if abhyasa.text == current_abhyasa_text {
+            abhyasa_has_changed = false;
         }
     }
 
+    // Keeping this outside the loop as this needs to be done only once
+    // after abhyasa has converged.
     let abhyasa = p.get(i)?;
     let dhatu = p.get(i_dhatu)?;
     if let Some(val) = KUH_CU
@@ -279,25 +315,6 @@ fn try_general_rules(p: &mut Prakriya, i: usize) -> Option<()> {
             p.run_at("7.4.62", i, |t| t.set_adi_char(val));
         }
     }
-
-    // no-hrasva is for pA --> apIpyat.
-    let abhyasa = p.get(i)?;
-    if al::is_dirgha(abhyasa.antya()?) && !abhyasa.has_tag(T::FlagNoHrasva) {
-        let val = al::to_hrasva(abhyasa.antya()?)?;
-        p.run_at("7.4.59", i, op::antya_char(&val));
-    }
-
-    if p.has(i, |t| t.has_antya('f')) {
-        p.run_at("7.4.66", i, op::antya("a"));
-    }
-
-    let dhatu = p.get(i_dhatu)?;
-    let last = p.terms().last()?;
-    if dhatu.has_u("i\\R") && last.has_tag(T::kit) && last.has_lakara(Lit) {
-        // IyatuH, IyuH
-        p.run_at("7.4.69", i, op::adi("I"));
-    }
-
     Some(())
 }
 
diff --git a/vidyut-prakriya/tests/integration/kashika_7_4.rs b/vidyut-prakriya/tests/integration/kashika_7_4.rs
@@ -694,7 +694,22 @@ fn sutra_7_4_66() {
     assert_has_lit(&[], &d("vftu~\\", Bhvadi), &["vavfte"]);
     assert_has_lit(&[], &d("vfDu~\\", Bhvadi), &["vavfDe"]);
     assert_has_lit(&[], &d("SfDu~\\", Bhvadi), &["SaSfDe"]);
-    // TODO: yaNluk examples.
+
+    assert_has_lat(
+        &[],
+        &yan_luk(&d("nftI~", Divadi)),
+        &[
+            "narInarti",
+            "narInartti",
+            "narInftIti",
+            "narinarti",
+            "narinartti",
+            "narinftIti",
+            "narnarti",
+            "narnartti",
+            "narnftIti",
+        ],
+    );
 }
 
 #[test]
diff --git a/vidyut-prakriya/tests/integration/prakriyas.rs b/vidyut-prakriya/tests/integration/prakriyas.rs
@@ -235,3 +235,64 @@ fn edha() {
     let p = ps.iter().find(|p| p.text() == "eDA").unwrap();
     assert_matches_prakriya(p, &[(A("6.1.101"), vec!["eD", "A", "", ""])]);
 }
+
+// Fixes https://github.com/ambuda-org/vidyut/issues/205
+//
+// Tests validate that the prakriya has 7.4.66 immediately followed by 1.1.51 as "nitya"
+// and that the resultant outputs are as expected for ऋकारान्त dhatus i.e. 'f' and 'F'
+#[test]
+#[allow(non_snake_case)]
+fn cakAra_etc() {
+    use Rule::Ashtadhyayi as A;
+
+    let args = tip_args(d("qukf\\Y", Tanadi), Lit);
+    let t = Tester::default();
+    let ps = t.derive_tinantas(&args);
+    let p = ps.iter().find(|p| p.text() == "cakAra").unwrap();
+
+    assert_matches_prakriya(
+        p,
+        &[
+            (A("7.2.115"), vec!["kf", "kAr", "a"]),
+            (A("7.4.66"), vec!["ka", "kAr", "a"]),
+            (A("1.1.51"), vec!["kar", "kAr", "a"]),
+            (A("7.4.60"), vec!["ka", "kAr", "a"]),
+            (A("7.4.62"), vec!["ca", "kAr", "a"]),
+        ],
+    );
+
+    // "f" is not in the end
+    let args = tip_args(d("kfpa~\\", Bhvadi), Lit);
+    let ps = t.derive_tinantas(&args);
+    let p = ps.iter().find(|p| p.text() == "cakxpe").unwrap();
+
+    assert_matches_prakriya(
+        p,
+        &[
+            (A("1.1.5"), vec!["kfp", "kfp", "e"]),
+            (A("7.4.60"), vec!["kf", "kfp", "e"]),
+            (A("7.4.66"), vec!["ka", "kfp", "e"]),
+            (A("1.1.51"), vec!["kar", "kfp", "e"]),
+            (A("7.4.60"), vec!["ka", "kfp", "e"]),
+            (A("7.4.62"), vec!["ca", "kfp", "e"]),
+            (A("8.2.18"), vec!["ca", "kxp", "e"]),
+        ],
+    );
+
+    // Try with dhatu having "F"
+    let args = tip_args(d("stFY", Kryadi), Lit);
+    let ps = t.derive_tinantas(&args);
+    let p = ps.iter().find(|p| p.text() == "tastare").unwrap();
+    assert_matches_prakriya(
+        p,
+        &[
+            (A("1.1.5"), vec!["stF", "stF", "e"]),
+            (A("7.4.11"), vec!["stF", "star", "e"]),
+            (A("7.4.61"), vec!["tF", "star", "e"]),
+            (A("7.4.66"), vec!["ta", "star", "e"]),
+            (A("1.1.51"), vec!["tar", "star", "e"]),
+            (A("7.4.60"), vec!["ta", "star", "e"]),
+            (A("6.4.126"), vec!["ta", "star", "e"]),
+        ],
+    );
+}
diff --git a/vidyut-prakriya/www/static/vidyut-prakriya-app.js b/vidyut-prakriya/www/static/vidyut-prakriya-app.js
@@ -467,7 +467,7 @@ const App = () => ({
 
     stepClasses(step) {
         const code = step.rule.code;
-        let minor = new Set(["1.3.1", "1.3.2", "1.3.3", "1.3.4", "1.3.5", "1.3.6", "1.3.7", "1.3.8", "1.3.9", "1.2.45", "3.4.114", "1.1.43",
+        let minor = new Set(["1.1.51", "1.3.1", "1.3.2", "1.3.3", "1.3.4", "1.3.5", "1.3.6", "1.3.7", "1.3.8", "1.3.9", "1.2.45", "3.4.114", "1.1.43",
             "1.4.58", "1.4.59", "1.4.60", "1.4.80", "6.1.4", "6.1.5", "8.4.68", "3.4.113", "2.3.48", "1.4.17", "2.3.49", "1.4.7",
         ]);
         let samjna = new Set (["1.2.46", "1.4.14", "3.1.32"]);
