2023-05-30 22:20:00

10 files changed, 205 insertions, 43 deletions

diff --git a/source/luametatex/source/lua/lmtnodelib.c b/source/luametatex/source/lua/lmtnodelib.c
index 58c3bb0a7..66cf528fc 100644
--- a/source/luametatex/source/lua/lmtnodelib.c
+++ b/source/luametatex/source/lua/lmtnodelib.c
@@ -2647,6 +2647,15 @@ static int nodelib_direct_getoptions(lua_State *L)
             case disc_node:
                 lua_pushinteger(L, disc_options(n));
                 return 1;
+            case glue_node:
+                lua_pushinteger(L, glue_options(n));
+                return 1;
+            case math_node:
+                lua_pushinteger(L, math_options(n));
+                return 1;
+            case penalty_node:
+                lua_pushinteger(L, penalty_options(n));
+                return 1;
             case simple_noad:
             case radical_noad:
             case fraction_noad:
@@ -2674,6 +2683,15 @@ static int nodelib_direct_setoptions(lua_State *L)
             case disc_node:
                 set_disc_options(n, lmt_tohalfword(L, 2));
                 break;
+            case glue_node:
+                tex_add_glue_option(n, lmt_tohalfword(L, 2));
+                return 1;
+            case math_node:
+                tex_add_math_option(n, lmt_tohalfword(L, 2));
+                return 1;
+            case penalty_node:
+                tex_add_penalty_option(n, lmt_tohalfword(L, 2));
+                return 1;
             case simple_noad:
             case radical_noad:
             case fraction_noad:
diff --git a/source/luametatex/source/lua/lmttexlib.c b/source/luametatex/source/lua/lmttexlib.c
index 1bfd2c38c..4f2ecbb5c 100644
--- a/source/luametatex/source/lua/lmttexlib.c
+++ b/source/luametatex/source/lua/lmttexlib.c
@@ -5015,6 +5015,24 @@ static int texlib_getglyphoptionvalues(lua_State *L)
     return 1;
 }
 
+static int texlib_getglueoptionvalues(lua_State *L)
+{
+    lua_createtable(L, 3, 0);
+    lua_set_string_by_index(L, glue_option_normal,        "normal");
+    lua_set_string_by_index(L, glue_option_no_auto_break, "noautobreak");
+    lua_set_string_by_index(L, glue_option_short_math,    "shortmath");
+    return 1;
+}
+
+static int texlib_getpenaltyoptionvalues(lua_State *L)
+{
+    lua_createtable(L, 3, 0);
+    lua_set_string_by_index(L, penalty_option_normal,        "normal");
+    lua_set_string_by_index(L, penalty_option_math_forward,  "mathforward");;
+    lua_set_string_by_index(L, penalty_option_math_backward, "mathbackward");
+    return 1;
+}
+
 static int texlib_getnoadoptionvalues(lua_State *L)
 {
     lua_createtable(L, 2, 37);
@@ -5780,6 +5798,9 @@ static const struct luaL_Reg texlib_function_list[] = {
     { "setrunstate",                texlib_setrunstate                },
     { "gethyphenationvalues",       texlib_gethyphenationvalues       },
     { "getglyphoptionvalues",       texlib_getglyphoptionvalues       },
+    { "getglueoptionvalues",        texlib_getglueoptionvalues        },
+    { "getmathoptionvalues",        texlib_getglueoptionvalues        },
+    { "getpenaltyoptionvalues",     texlib_getpenaltyoptionvalues     },
     { "getnoadoptionvalues",        texlib_getnoadoptionvalues        },
     { "getdiscoptionvalues",        texlib_getdiscoptionvalues        },
     { "getlistanchorvalues",        texlib_getlistanchorvalues        },
diff --git a/source/luametatex/source/luametatex.h b/source/luametatex/source/luametatex.h
index d9df0e14c..a6e9b5295 100644
--- a/source/luametatex/source/luametatex.h
+++ b/source/luametatex/source/luametatex.h
@@ -92,7 +92,7 @@
 # define luametatex_version          210
 # define luametatex_revision         9
 # define luametatex_version_string   "2.10.09"
-# define luametatex_development_id   20230529
+# define luametatex_development_id   20230530
 
 # define luametatex_name_camelcase   "LuaMetaTeX"
 # define luametatex_name_lowercase   "luametatex"
diff --git a/source/luametatex/source/tex/texcommands.c b/source/luametatex/source/tex/texcommands.c
index 26ae7cef9..1423c80d0 100644
--- a/source/luametatex/source/tex/texcommands.c
+++ b/source/luametatex/source/tex/texcommands.c
@@ -167,6 +167,7 @@ void tex_initialize_commands(void)
         tex_primitive(luatex_command, "preinlinepenalty",               internal_int_cmd,       pre_inline_penalty_code,                  internal_int_base);
         tex_primitive(luatex_command, "postshortinlinepenalty",         internal_int_cmd,       post_short_inline_penalty_code,           internal_int_base);
         tex_primitive(luatex_command, "preshortinlinepenalty",          internal_int_cmd,       pre_short_inline_penalty_code,            internal_int_base);
+        tex_primitive(luatex_command, "shortinlineorphanpenalty",       internal_int_cmd,       short_inline_orphan_penalty_code,         internal_int_base);
         tex_primitive(tex_command,    "pretolerance",                   internal_int_cmd,       pre_tolerance_code,                       internal_int_base);
         tex_primitive(tex_command,    "relpenalty",                     internal_int_cmd,       post_relation_penalty_code,               internal_int_base); /*tex For old times sake. */
         tex_primitive(tex_command,    "righthyphenmin",                 internal_int_cmd,       right_hyphen_min_code,                    internal_int_base);
diff --git a/source/luametatex/source/tex/texequivalents.h b/source/luametatex/source/tex/texequivalents.h
index b129cb047..384a17e06 100644
--- a/source/luametatex/source/tex/texequivalents.h
+++ b/source/luametatex/source/tex/texequivalents.h
@@ -437,6 +437,7 @@ typedef enum int_codes {
     post_inline_penalty_code,           /*tex penalty for breaking just after an inlined formula */
     pre_short_inline_penalty_code,      /*tex penalty for breaking just before a single character inlined formula */
     post_short_inline_penalty_code,     /*tex penalty for breaking just after a single character inlined formula */
+    short_inline_orphan_penalty_code,
     inter_line_penalty_code,            /*tex additional penalty between lines */
     double_hyphen_demerits_code,        /*tex demerits for double hyphen break */
     final_hyphen_demerits_code,         /*tex demerits for final hyphen break */
@@ -1411,6 +1412,7 @@ extern void tex_forced_word_define (int g, halfword p, singleword flag, halfword
 # define post_inline_penalty_par         count_parameter(post_inline_penalty_code)
 # define pre_short_inline_penalty_par    count_parameter(pre_short_inline_penalty_code)
 # define post_short_inline_penalty_par   count_parameter(post_short_inline_penalty_code)
+# define short_inline_orphan_penalty_par count_parameter(short_inline_orphan_penalty_code)
 
 # define local_interline_penalty_par     count_parameter(local_interline_penalty_code)
 # define local_broken_penalty_par        count_parameter(local_broken_penalty_code)
diff --git a/source/luametatex/source/tex/texlinebreak.c b/source/luametatex/source/tex/texlinebreak.c
index 0c2445ffe..93a537ca7 100644
--- a/source/luametatex/source/tex/texlinebreak.c
+++ b/source/luametatex/source/tex/texlinebreak.c
@@ -2051,7 +2051,7 @@ static void tex_aux_try_break(
             } else {
                 demerits = demerits * demerits;
             }
-            if (penalty != 0) {
+            if (penalty) {
                 if (penalty > 0) {
                     demerits += (penalty * penalty);
                 } else if (penalty > eject_penalty) {
@@ -2198,6 +2198,30 @@ inline static halfword tex_aux_upcoming_penalty(halfword p) {
 
 # define max_prev_graf (max_integer/2)
 
+static inline int tex_aux_short_math(halfword m) {
+    return m && node_subtype(m) == begin_inline_math && math_penalty(m) > 0 && tex_has_math_option(m, glue_option_short_math);
+}
+
+static inline void tex_aux_adapt_short_math_penalty(halfword m, halfword p1, halfword p2) {
+    if (p1 > math_penalty(m)) {
+        math_penalty(m) = p1;
+    }
+    if (p2 > math_penalty(m)) {
+        math_penalty(m) = p2;
+    }
+}
+
+static inline halfword tex_aux_backtrack_over_math(halfword m) 
+{
+    if (node_subtype(m) == end_inline_math) { 
+        do { 
+            m = node_prev(m);
+        } while (m && node_type(m) != math_node);
+    }
+    return m;
+}
+
+
 void tex_do_line_break(line_break_properties *properties)
 {
     /*tex Miscellaneous nodes of temporary interest. */
@@ -2256,7 +2280,7 @@ void tex_do_line_break(line_break_properties *properties)
         also skip a penalty in the list.
 
     */
-    if (properties->orphan_penalties || properties->orphan_penalty) {
+    if (properties->orphan_penalties || properties->orphan_penalty || short_inline_orphan_penalty_par) {
         halfword current = node_prev(properties->parfill_right_skip);
         if (current) {
             /*tex Skip over trailing glue and penalties. */
@@ -2272,37 +2296,119 @@ void tex_do_line_break(line_break_properties *properties)
             }
           INJECT:
             if (properties->orphan_penalties) {
-                /*tex Inject specified penalties before spaces. */
+                /*tex 
+                    Inject specified penalties before spaces. When wwe see a math node with a penalty
+                    set then we take the max and jump over a (preceding) skip. Maybe at some point 
+                    the |short_inline_orphan_penalty_par| value will also move into the par state.
+                */
                 int n = specification_count(properties->orphan_penalties);
                 if (n > 0) {
+                    int skip = 0;
                     halfword i = 0;
                     while (current) {
-                        if (node_type(current) == glue_node) {
-                            switch (node_subtype(current)) {
-                                case space_skip_glue:
-                                case xspace_skip_glue:
-                                case zero_space_skip_glue:
-                                    current = tex_aux_inject_orphan_penalty(current, tex_get_specification_penalty(properties->orphan_penalties, ++i));
+                        switch (node_type(current)) { 
+                            case glue_node:
+                                switch (node_subtype(current)) {
+                                    case space_skip_glue:
+                                    case xspace_skip_glue:
+                                    case zero_space_skip_glue:
+                                        if (skip) { 
+                                            skip = 0;
+                                        } else {
+                                            current = tex_aux_inject_orphan_penalty(current, tex_get_specification_penalty(properties->orphan_penalties, ++i));
+                                        }
+                                        if (i == n) {
+                                            goto ALLDONE;
+                                        } else {
+                                            break;
+                                        }
+                                }
+                                break;
+                            case math_node:
+                                current = tex_aux_backtrack_over_math(current); 
+                                if (tex_aux_short_math(current)) { 
+                                    halfword p = tex_get_specification_penalty(properties->orphan_penalties, ++i);
+                                    tex_aux_adapt_short_math_penalty(current, short_inline_orphan_penalty_par, p);
                                     if (i == n) {
                                         goto ALLDONE;
                                     } else {
-                                        break;
+                                        skip = 1;
                                     }
-                            }
+                                } else { 
+                                    goto ALLDONE;
+                                }
+                                break;
+                            default: 
+                                skip = 0;
+                                break;
                         }
                         current = node_prev(current);
                     }
                 }
-            } else {
+            } else if (properties->orphan_penalty) {
+                /*tex
+                    We inject a penalty before the space but we need to intercept the math penalty
+                    that actually is set on the math mode.  If no math orphan penalty is set of when 
+                    we have wider math then we assume it's okay. We don't want interference in math
+                    penalties. 
+                    
+                */
                 while (current) {
-                    if (node_type(current) == glue_node) {
-                        switch (node_subtype(current)) {
-                            case space_skip_glue:
-                            case xspace_skip_glue:
-                            case zero_space_skip_glue:
-                                tex_aux_inject_orphan_penalty(current, properties->orphan_penalty);
-                                goto ALLDONE;
-                        }
+                    switch (node_type(current)) { 
+                        case glue_node:
+                            switch (node_subtype(current)) {
+                                case space_skip_glue:
+                                case xspace_skip_glue:
+                                case zero_space_skip_glue:
+                                    tex_aux_inject_orphan_penalty(current, properties->orphan_penalty);
+                                    goto ALLDONE;
+                                default: 
+                                    /* maybe we should always quit here */
+                                    break;
+                            }
+                            break;
+                        case math_node:
+                            current = tex_aux_backtrack_over_math(current); 
+                            if (tex_aux_short_math(current)) { 
+                                tex_aux_adapt_short_math_penalty(current, short_inline_orphan_penalty_par, properties->orphan_penalty);
+                            }
+                            goto ALLDONE;
+                        case disc_node: 
+                            /*
+                                This is (or has been) actually an old \CONTEXT\ feature doen in \LUA,
+                                so what should we do here: set the penalty and quit or maybe run till we 
+                                hit a non glyph, disc or font kern? Hyphens already get penalties. So,
+                                we do nothong.
+                            */
+                            break;
+                    }
+                    current = node_prev(current);
+                }
+            } else if (short_inline_orphan_penalty_par) {
+                /*tex
+                    Short formulas at the end of a line are normally not followed by something other 
+                    than punctuation. In practice one can set this penalty to e.g. a relatively low 
+                    200 to get the desired effect. We definitely quit on a space and take for granted 
+                    what comes before we see the formula. 
+                    
+                */
+                while (current) {
+                    switch (node_type(current)) { 
+                        case glue_node:
+                            switch (node_subtype(current)) {
+                                case space_skip_glue:
+                                case xspace_skip_glue:
+                                case zero_space_skip_glue:
+                                    goto ALLDONE;
+                            }
+                            break;
+                        case math_node:
+                            current = tex_aux_backtrack_over_math(current); 
+                            if (tex_aux_short_math(current)) { 
+                                tex_aux_adapt_short_math_penalty(current, short_inline_orphan_penalty_par, 0);
+                            }
+                            goto ALLDONE;
+                            
                     }
                     current = node_prev(current);
                 }
diff --git a/source/luametatex/source/tex/texmath.c b/source/luametatex/source/tex/texmath.c
index e2b4f9c39..923ffa56e 100644
--- a/source/luametatex/source/tex/texmath.c
+++ b/source/luametatex/source/tex/texmath.c
@@ -5010,6 +5010,8 @@ void tex_run_math_shift(void)
                         if (post_short_inline_penalty_par != max_integer) {
                             math_penalty(endmath) = post_short_inline_penalty_par;
                         }
+                        tex_add_math_option(beginmath, glue_option_short_math);
+                        tex_add_math_option(endmath, glue_option_short_math);
                     }
                     cur_list.space_factor = default_space_factor;
                     mathleft = cur_list.math_begin;
diff --git a/source/luametatex/source/tex/texmlist.c b/source/luametatex/source/tex/texmlist.c
index 1b9201172..d91ee50ae 100644
--- a/source/luametatex/source/tex/texmlist.c
+++ b/source/luametatex/source/tex/texmlist.c
@@ -1981,7 +1981,7 @@ void tex_run_mlist_to_hlist(halfword mlist, halfword penalties, halfword style,
              node_next(temp_head) = null;
         }
         if (penalties) { // && tex_in_main_math_style(style)  
-            /*tex This makes no sense in display math not in script styles. */
+            /*tex This makes no sense in display math nor in script styles. */
             switch (style) {
                 case text_style:        
                 case cramped_text_style:        
@@ -1992,8 +1992,8 @@ void tex_run_mlist_to_hlist(halfword mlist, halfword penalties, halfword style,
                             halfword i = 1;
                             while (h && i <= n) {
                                 if (tex_aux_is_math_penalty(h)) {
-                                    penalty_amount(h) += tex_get_specification_penalty(math_forward_penalties_par, i);
-                                    ++i;
+                                    penalty_amount(h) += tex_get_specification_penalty(math_forward_penalties_par, i++);
+                                    tex_add_penalty_option(h, penalty_option_math_forward);
                                 }
                                 h = node_next(h);
                             }
@@ -2006,8 +2006,8 @@ void tex_run_mlist_to_hlist(halfword mlist, halfword penalties, halfword style,
                             halfword i = 1;
                             while (t && i <= n) {
                                 if (tex_aux_is_math_penalty(t)) {
-                                    penalty_amount(t) += tex_get_specification_penalty(math_backward_penalties_par, i);
-                                    ++i;
+                                    penalty_amount(t) += tex_get_specification_penalty(math_backward_penalties_par, i++);
+                                    tex_add_penalty_option(t, penalty_option_math_backward);
                                 }
                                 t = node_prev(t);
                             }
@@ -7304,13 +7304,13 @@ static void tex_mlist_to_hlist_finalize_list(mliststate *state)
             recent_subtype = node_subtype(recent);
             /* todo: maybe also check the mainclass of the recent  */
             if ((recent_type != penalty_node) && ! (recent_type == simple_noad && tex_math_has_class_option(recent_subtype, omit_penalty_class_option))) {
-                halfword z = tex_new_penalty_node(post_penalty, math_post_penalty_subtype);
-                tex_attach_attribute_list_copy(z, current);
-                tex_couple_nodes(p, z);
-                p = z;
+                halfword penalty = tex_new_penalty_node(post_penalty, math_post_penalty_subtype);
+                tex_attach_attribute_list_copy(penalty, current);
+                tex_couple_nodes(p, penalty);
+                p = penalty;
                 if (tracing_math_par >= 2) {
                     tex_begin_diagnostic();
-                    tex_print_format("[math: post penalty, left %n, right %n, amount %i]", recent_subtype, current_subtype, penalty_amount(z));
+                    tex_print_format("[math: post penalty, left %n, right %n, amount %i]", recent_subtype, current_subtype, penalty_amount(penalty));
                     tex_end_diagnostic();
                 }
             }
@@ -7330,11 +7330,11 @@ static void tex_mlist_to_hlist_finalize_list(mliststate *state)
         recent_plus_glyph = current_plus_glyph;
         // if (first && recent_left_slack) {
         if (p == temp_head && recent_left_slack) {
-            halfword k = tex_new_kern_node(-recent_left_slack, horizontal_math_kern_subtype);
-            halfword h = node_next(temp_head);
-            tex_attach_attribute_list_copy(k, p);
-            tex_couple_nodes(k, h);
-            node_next(temp_head) = k;
+            halfword kern = tex_new_kern_node(-recent_left_slack, horizontal_math_kern_subtype);
+            halfword head = node_next(temp_head);
+            tex_attach_attribute_list_copy(kern, p);
+            tex_couple_nodes(kern, head);
+            node_next(temp_head) = kern;
             if (tracing_math_par >= 2) {
                 tex_begin_diagnostic();
                 tex_print_format("[math: nilling recent left slack %p]", recent_left_slack);
@@ -7344,10 +7344,10 @@ static void tex_mlist_to_hlist_finalize_list(mliststate *state)
         recent = current;
         current = node_next(current);
         if (! current && recent_right_slack) {
-            halfword k = tex_new_kern_node(-recent_right_slack, horizontal_math_kern_subtype);
-            tex_attach_attribute_list_copy(k, p);
-            tex_couple_nodes(p, k);
-            p = k;
+            halfword kern = tex_new_kern_node(-recent_right_slack, horizontal_math_kern_subtype);
+            tex_attach_attribute_list_copy(kern, p);
+            tex_couple_nodes(p, kern);
+            p = kern;
             if (tracing_math_par >= 2) {
                 tex_begin_diagnostic();
                 tex_print_format("[math: nilling recent right slack %p]", recent_right_slack);
diff --git a/source/luametatex/source/tex/texnodes.h b/source/luametatex/source/tex/texnodes.h
index 80ab40f03..3550e7345 100644
--- a/source/luametatex/source/tex/texnodes.h
+++ b/source/luametatex/source/tex/texnodes.h
@@ -422,8 +422,19 @@ typedef enum attribute_subtypes {
     with arguments.
 */
 
-# define penalty_node_size 3
-# define penalty_amount(a) vlink(a,2)
+# define penalty_node_size  3
+# define penalty_amount(a)  vlink(a,2)
+# define penalty_options(a) vinfo(a,2)
+
+inline static void tex_add_penalty_option    (halfword a, halfword r) { penalty_options(a) |= r; }
+inline static void tex_remove_penalty_option (halfword a, halfword r) { penalty_options(a) &= ~(r | penalty_options(a)); }
+inline static int  tex_has_penalty_option    (halfword a, halfword r) { return (penalty_options(a) & r) == r; }
+
+typedef enum penalty_option_codes {
+    penalty_option_normal        = 0x0000,
+    penalty_option_math_forward  = 0x0001,
+    penalty_option_math_backward = 0x0002,
+} penalty_option_codes; 
 
 typedef enum penalty_subtypes {
     user_penalty_subtype,
@@ -522,6 +533,7 @@ typedef enum glue_option_codes {
  // glue_force_auto_break     = 0x0001,
  // glue_originates_in_math   = 0x0002,
     glue_option_no_auto_break = 0x0001,
+    glue_option_short_math    = 0x0002,
 } glue_option_codes; 
 
 typedef enum math_subtypes {
diff --git a/source/luametatex/source/tex/texpackaging.c b/source/luametatex/source/tex/texpackaging.c
index 83ace07fa..9f66232a7 100644
--- a/source/luametatex/source/tex/texpackaging.c
+++ b/source/luametatex/source/tex/texpackaging.c
@@ -2781,7 +2781,7 @@ static halfword tex_aux_depth_correction(halfword b, const line_break_properties
             p = tex_new_param_glue_node(line_skip_code, line_skip_glue);
         } else {
             p = tex_new_param_glue_node(baseline_skip_code, baseline_skip_glue);
-            glue_amount(p) = d;
+            glue_amount(p) = d; /* we keep the stretch and shrink */
         }
     }
     return p;