Fix NABC inter-syllable overflow spacing and add nabcintersyllablemingap

tests/tex-output/bugs/fix-1715/puer-natus-mingap-0.tex

@@ -0,0 +1,41 @@
+% !TEX TS-program = LuaLaTeX+se
+% !TEX encoding = UTF-8
+
+% Test for issue #1715: nabcintersyllablemingap = 0pt
+% With zero mingap, the overflow model only pushes when NABC physically
+% overflows the notes box — no extra minimum separation enforced.
+
+\documentclass[11pt]{article}
+\usepackage{fontspec}
+\usepackage{geometry}
+\geometry{a4paper}
+\usepackage[allowdeprecated=false]{gregoriotex}
+\usepackage{fullpage}
+\setmainfont[
+    Path = ../../../../fonts/ ,
+    Extension = .otf ,
+    UprightFont = *-Regular ,
+    UprightFeatures = { SmallCapsFont = *SC-Regular } ,
+    BoldFont = *-Bold ,
+    BoldFeatures = { SmallCapsFont = *SC-Bold } ,
+    ItalicFont = *-Italic ,
+    ItalicFeatures = { SmallCapsFont = *SC-Italic } ,
+    BoldItalicFont = *-BoldItalic ,
+    BoldItalicFeatures = { SmallCapsFont = *SC-BoldItalic } ,
+    Ligatures = TeX
+]{Alegreya}
+
+\grechangedim{baselineskip}{65pt}{scalable}
+\gresetnabcalignment{neume}
+\gresetnabcfont[1]{grelaon}{8}
+
+% Override: disable mingap entirely
+\grechangedim{nabcintersyllablemingap}{0pt}{scalable}
+
+\listfiles
+\begin{document}
+
+\section*{Puer natus est — mingap = 0pt}
+\gregorioscore[a]{puer-natus}
+
+\end{document}

tests/tex-output/bugs/fix-1715/puer-natus-mingap-double.tex

@@ -0,0 +1,41 @@
+% !TEX TS-program = LuaLaTeX+se
+% !TEX encoding = UTF-8
+
+% Test for issue #1715: nabcintersyllablemingap = 0.12cm (2x default)
+% Doubling the mingap should produce visibly wider NABC inter-syllable
+% separation compared to the default 0.06cm.
+
+\documentclass[11pt]{article}
+\usepackage{fontspec}
+\usepackage{geometry}
+\geometry{a4paper}
+\usepackage[allowdeprecated=false]{gregoriotex}
+\usepackage{fullpage}
+\setmainfont[
+    Path = ../../../../fonts/ ,
+    Extension = .otf ,
+    UprightFont = *-Regular ,
+    UprightFeatures = { SmallCapsFont = *SC-Regular } ,
+    BoldFont = *-Bold ,
+    BoldFeatures = { SmallCapsFont = *SC-Bold } ,
+    ItalicFont = *-Italic ,
+    ItalicFeatures = { SmallCapsFont = *SC-Italic } ,
+    BoldItalicFont = *-BoldItalic ,
+    BoldItalicFeatures = { SmallCapsFont = *SC-BoldItalic } ,
+    Ligatures = TeX
+]{Alegreya}
+
+\grechangedim{baselineskip}{65pt}{scalable}
+\gresetnabcalignment{neume}
+\gresetnabcfont[1]{grelaon}{8}
+
+% Override: double the default mingap (0.06cm -> 0.12cm)
+\grechangedim{nabcintersyllablemingap}{0.12cm}{scalable}
+
+\listfiles
+\begin{document}
+
+\section*{Puer natus est — mingap = 0.12cm}
+\gregorioscore[a]{puer-natus}
+
+\end{document}

tests/tex-output/bugs/fix-1715/puer-natus-mingap-extreme.tex

@@ -0,0 +1,42 @@
+% !TEX TS-program = LuaLaTeX+se
+% !TEX encoding = UTF-8
+
+% Test for issue #1715: nabcintersyllablemingap = 1cm (exaggerated)
+% An absurdly large mingap to stress-test the overflow model. The NABC
+% glyphs should be pushed far apart, likely causing line breaks and
+% visual distortion — confirms the parameter has unbounded effect.
+
+\documentclass[11pt]{article}
+\usepackage{fontspec}
+\usepackage{geometry}
+\geometry{a4paper}
+\usepackage[allowdeprecated=false]{gregoriotex}
+\usepackage{fullpage}
+\setmainfont[
+    Path = ../../../../fonts/ ,
+    Extension = .otf ,
+    UprightFont = *-Regular ,
+    UprightFeatures = { SmallCapsFont = *SC-Regular } ,
+    BoldFont = *-Bold ,
+    BoldFeatures = { SmallCapsFont = *SC-Bold } ,
+    ItalicFont = *-Italic ,
+    ItalicFeatures = { SmallCapsFont = *SC-Italic } ,
+    BoldItalicFont = *-BoldItalic ,
+    BoldItalicFeatures = { SmallCapsFont = *SC-BoldItalic } ,
+    Ligatures = TeX
+]{Alegreya}
+
+\grechangedim{baselineskip}{65pt}{scalable}
+\gresetnabcalignment{neume}
+\gresetnabcfont[1]{grelaon}{8}
+
+% Override: absurdly large mingap (stress test)
+\grechangedim{nabcintersyllablemingap}{1cm}{scalable}
+
+\listfiles
+\begin{document}
+
+\section*{Puer natus est — mingap = 1cm (extreme)}
+\gregorioscore[a]{puer-natus}
+
+\end{document}

tests/tex-output/bugs/fix-1715/puer-natus-mingap-max.tex

@@ -0,0 +1,41 @@
+% !TEX TS-program = LuaLaTeX+se
+% !TEX encoding = UTF-8
+
+% Test for issue #1715: nabcintersyllablemingap = 0.24cm (= intersyllablespacenotes)
+% Setting mingap to the full inter-syllable space is an extreme value that
+% should produce maximum NABC separation — useful for visual comparison.
+
+\documentclass[11pt]{article}
+\usepackage{fontspec}
+\usepackage{geometry}
+\geometry{a4paper}
+\usepackage[allowdeprecated=false]{gregoriotex}
+\usepackage{fullpage}
+\setmainfont[
+    Path = ../../../../fonts/ ,
+    Extension = .otf ,
+    UprightFont = *-Regular ,
+    UprightFeatures = { SmallCapsFont = *SC-Regular } ,
+    BoldFont = *-Bold ,
+    BoldFeatures = { SmallCapsFont = *SC-Bold } ,
+    ItalicFont = *-Italic ,
+    ItalicFeatures = { SmallCapsFont = *SC-Italic } ,
+    BoldItalicFont = *-BoldItalic ,
+    BoldItalicFeatures = { SmallCapsFont = *SC-BoldItalic } ,
+    Ligatures = TeX
+]{Alegreya}
+
+\grechangedim{baselineskip}{65pt}{scalable}
+\gresetnabcalignment{neume}
+\gresetnabcfont[1]{grelaon}{8}
+
+% Override: set mingap to full intersyllablespacenotes value (extreme)
+\grechangedim{nabcintersyllablemingap}{0.24cm}{scalable}
+
+\listfiles
+\begin{document}
+
+\section*{Puer natus est — mingap = 0.24cm}
+\gregorioscore[a]{puer-natus}
+
+\end{document}

tests/tex-output/bugs/fix-1715/puer-natus.gabc

@@ -0,0 +1,17 @@
+name: Puer natus est;
+annotation: Intr.;
+annotation: VII;
+nabc-lines: 2;
+%%
+(c3) Pu(ei|peG|`````tvhl```peSlsm2lsim8)er(i|unhk|vilse4) *()
+na(iji|to|tolse4)tus(h|un|ta) est(hhh|ts|ts)
+no(ih/ji|pf|pflsl3lsp1lsc1)bis,(i|unlst2|vi) (,)
+et(fi~|ta>|ta>lsi7) fí(iji|to|to)li(hf|cl|cllsc3)us(f|un|ta)
+da(h|unlst2|vi-|hi|pe|pe)tus(h|un|ta) est(h|un|ta) no(hihh|tr|tr)bis:(efe|ta>``unlsa2|tolst2) (;) cu(e|puhd|talse4)jus(f|pu|vi) im(h|unhh|vi)pé(gi!jk|sclst2vihl|peShjppt2lsi7)ri(ih|cl|cllsc3)um(h|un|ta) (,?)
+su(h|un|ta)per(h|un|ta) hú(ih/ji|pf|pflsl3lsm4lsi7)me(hg|clG|cl-lst2)rum(hhh|ts|ts)
+e(hf|clGlsa5|cl-lst2|hg/hgf~|po``vi>|pf>lsc2)jus:(gf|clG|cl-) (;)
+et(fhg|cl>|tolsc2lsi7) vo(h|un|vi)cá(hji|to|tolse4)bi(h|un|ta)tur(hhh|ts|ts)
+no(h|un|ta)men(hhh|ts|ts) e(hih|trlst8`vi>|toS2lssm2lse4|hgf~||cl->)jus,(gf|clG|cl-) (,)
+ma(hj|pe>1lsc3ltqm4|pe>1lss4)gni(i|un|vi)
+con(fh~|ta>|ta>lsiv8)sí(h|un|vi)lii(hh|tssun1|ds|hf||cl-)
+An(fhf!gwh|peG``ql>ppn1ltsj3ltqm3|toSlse4ql>lss3)ge(efe|toGlsa5|toS)lus.(e|un|ta) <i>Ps.</i>(::) Can(hg~||vi>lss6)tá(hi||pe)te(i||vi) Dó(i||vi)mi(i||vi)no(i||vi) cán(ik||pe)ti(j||vi)cum(j||vi) no(ji||cl)vum:(ij||pe) *(:) qui(ig||cl)a(hi||pe) mi(i||vi)ra(i||vi)bí(jwk||qi)li(i||vi)a(h||ta) fe(hhh||ts)cit.(fef||cl-vi-lsim8) (::)

tests/tex-output/bugs/fix-1715/puer-natus.tex

@@ -0,0 +1,42 @@
+% !TEX TS-program = LuaLaTeX+se
+% !TEX encoding = UTF-8
+
+% Regression test for issue #1715: excessive inter-syllable spacing when NABC
+% extends past the notes box (extrakern mechanism).
+%
+% Puer natus est (Introit, Mode VII) with two NABC voices.
+% With the fix, the gap between syllables "Pu" and "er" should be normal
+% (no extrakern added, since the natural inter-syllable space already
+% prevents NABC overlap).
+
+\documentclass[11pt]{article}
+\usepackage{fontspec}
+\usepackage{geometry}
+\geometry{a4paper}
+\usepackage[allowdeprecated=false]{gregoriotex}
+\usepackage{fullpage}
+\setmainfont[
+    Path = ../../../../fonts/ ,
+    Extension = .otf ,
+    UprightFont = *-Regular ,
+    UprightFeatures = { SmallCapsFont = *SC-Regular } ,
+    BoldFont = *-Bold ,
+    BoldFeatures = { SmallCapsFont = *SC-Bold } ,
+    ItalicFont = *-Italic ,
+    ItalicFeatures = { SmallCapsFont = *SC-Italic } ,
+    BoldItalicFont = *-BoldItalic ,
+    BoldItalicFeatures = { SmallCapsFont = *SC-BoldItalic } ,
+    Ligatures = TeX
+]{Alegreya}
+
+\grechangedim{baselineskip}{65pt}{scalable}
+\gresetnabcalignment{neume}
+\gresetnabcfont[1]{grelaon}{8}
+
+\listfiles
+\begin{document}
+
+\section*{Puer natus est — regression test for \#1715}
+\gregorioscore[a]{puer-natus}
+
+\end{document}