Add support for glue length in parskip (#12867)

development/FORMAT

@@ -7,6 +7,14 @@ changes happened in particular if possible. A good example would be
 
 -----------------------
 
+2024-06-01 Jürgen Spitzmüller <spitz@lyx.org> 
+	* Format incremented to 622: Allow glue length (skip) in parskip setting.
+
+2024-05-13 Jürgen Spitzmüller <spitz@lyx.org> 
+	* Format incremented to 621: Escape some special chars (#, %, \) in URL
+	  with hyperref. Previous to this change, the user had to escape this
+	  themselves.
+
 2023-09-29 Jürgen Spitzmüller <spitz@lyx.org> 
 	* Format incremented to 620: Add InsetBox "default" framecolor ("foreground"
 	  rather than "black" in GUI). This aligns better with dark mode.

lib/lyx2lyx/lyx_2_5.py

@@ -26,10 +26,10 @@ from datetime import (datetime, date, time)
 
 # Uncomment only what you need to import, please.
 
-from parser_tools import (find_end_of_inset, find_end_of_layout, find_token, find_re)
+from parser_tools import (find_end_of_inset, find_end_of_layout, find_token, find_re, get_value)
 #    count_pars_in_inset, del_complete_lines, del_token, find_end_of,
 #    find_token_backwards, find_token_exact, get_bool_value,
-#    get_containing_inset, get_containing_layout, get_option_value, get_value,
+#    get_containing_inset, get_containing_layout, get_option_value,
 #    get_quoted_value, is_in_inset,
 #    del_value, 
 #    find_complete_lines,
@@ -37,9 +37,10 @@ from parser_tools import (find_end_of_inset, find_end_of_layout, find_token, fin
 #    set_bool_value
 #    find_tokens, check_token
 
-#from lyx2lyx_tools import (put_cmd_in_ert, add_to_preamble, insert_to_preamble, lyx2latex,
-#                           revert_language, revert_flex_inset, str2bool)
-#  revert_font_attrs, latex_length
+from lyx2lyx_tools import (add_to_preamble, latex_length)
+#  put_cmd_in_ert, insert_to_preamble, lyx2latex,
+#  revert_language, revert_flex_inset, str2bool,
+#  revert_font_attrs,
 #  get_ert, lyx2verbatim, length_in_bp, convert_info_insets
 #  revert_flex_inset, hex2ratio
 
@@ -167,17 +168,44 @@ def revert_url_escapes2(document):
             document.body[bs] = "\\backslash\\backslash"
             i = bs + 1
 
+
+def revert_glue_parskip(document):
+    """Revert parskip with glue length to user preamble."""
+
+    i = find_token(document.header, "\\paragraph_separation skip", 0)
+    if i == -1:
+        return
+
+    j = find_token(document.header, "\\defskip", 0)
+    if j == -1:
+        document.warning("Malformed LyX document! Missing \\defskip.")
+        return
+
+    val = get_value(document.header, "\\defskip", j)
+
+    if val.find("+") == -1 and val.find("-", 1) == -1:
+        # not a glue length
+        return
+
+    add_to_preamble(document, ["\\usepackage[skip={" + latex_length(val)[1] + "}]{parskip}"])
+
+    document.header[i] = "\\paragraph_separation indent"
+    document.header[j] = "\\paragraph_indentation default"
+
+
 ##
 # Conversion hub
 #
 
 supported_versions = ["2.5.0", "2.5"]
 convert = [
-           [621, [convert_url_escapes, convert_url_escapes2]]
+           [621, [convert_url_escapes, convert_url_escapes2]],
+           [622, []]
           ]
 
 
-revert =  [[620, [revert_url_escapes2, revert_url_escapes]]
+revert =  [[621, [revert_glue_parskip]],
+           [620, [revert_url_escapes2, revert_url_escapes]]
           ]
 
 

src/BufferParams.cpp

@@ -2189,8 +2189,13 @@ bool BufferParams::writeLaTeX(otexstream & os, LaTeXFeatures & features,
 		} else {
 			// load parskip package with required options
 			string psopts;
-			if (!psopt.empty())
+			if (!psopt.empty()) {
+				if (contains(psopt, ' '))
+					// glue length has spaces: embrace
+					psopts = "skip={" + psopt + "}";
+				else
 					psopts = "skip=" + psopt;
+			}
 			string const xpsopts = getPackageOptions("parskip");
 			if (!xpsopts.empty()) {
 				if (!psopts.empty())

src/frontends/qt/GuiDocument.cpp

@@ -892,8 +892,10 @@ GuiDocument::GuiDocument(GuiView & lv)
 		textLayoutModule->lspacingLE));
 	textLayoutModule->indentLE->setValidator(new LengthValidator(
 		textLayoutModule->indentLE, false));
-	textLayoutModule->skipLE->setValidator(new LengthValidator(
-		textLayoutModule->skipLE, false));
+	// parskip accepts glue length
+	LengthValidator * skipLEValidator = new LengthValidator(textLayoutModule->skipLE, false);
+	skipLEValidator->setBottom(GlueLength());
+	textLayoutModule->skipLE->setValidator(skipLEValidator);
 
 	textLayoutModule->indentCO->addItem(qt_("Default"), toqstr("default"));
 	textLayoutModule->indentCO->addItem(qt_("Custom"), toqstr("custom"));

src/tex2lyx/Preamble.cpp

@@ -1745,8 +1745,13 @@ void Preamble::handle_package(Parser &p, string const & name,
 				h_defskip = "bigskip";
 			else if (opts == "skip=\\baselineskip")
 				h_defskip = "fullline";
-			else
-				h_defskip = "opts";
+			else {
+				// get value, unbraced
+				string length = rtrim(ltrim(token(opts, '=', 1), "{"), "}");
+				// transform glue length if we have one
+				is_glue_length(length);
+				h_defskip = length;
+			}
 			h_paragraph_separation = "skip";
 		}
 	}

src/tex2lyx/tex2lyx.h

@@ -46,6 +46,7 @@ extern std::string rgbcolor2code(std::string const & name);
 
 /// in text.cpp
 std::string translate_len(std::string const &);
+bool is_glue_length(std::string & length);
 
 void parse_text(Parser & p, std::ostream & os, unsigned flags, bool outer,
 		Context & context, std::string const & rdelim = "",

src/tex2lyx/text.cpp

@@ -608,6 +608,32 @@ string translate_len(string const & length)
 	return length;
 }
 
+bool is_glue_length(string & length)
+{
+	// check for glue lengths
+	bool is_gluelength = false;
+	string gluelength = length;
+	string::size_type i = length.find(" minus");
+	if (i == string::npos) {
+		i = length.find(" plus");
+		if (i != string::npos)
+			is_gluelength = true;
+	} else
+		is_gluelength = true;
+	// if yes transform "9xx minus 8yy plus 7zz"
+	// to "9xx-8yy+7zz"
+	if (is_gluelength) {
+		i = gluelength.find(" minus");
+		if (i != string::npos)
+			gluelength.replace(i, 7, "-");
+		i = gluelength.find(" plus");
+		if (i != string::npos)
+			gluelength.replace(i, 6, "+");
+		length = gluelength;
+	}
+	return is_gluelength;
+}
+
 
 namespace {
 
@@ -6039,25 +6065,8 @@ void parse_text(Parser & p, ostream & os, unsigned flags, bool outer,
 			}
 
 			// check for glue lengths
-			bool is_gluelength = false;
 			string gluelength = length;
-			string::size_type i = length.find(" minus");
-			if (i == string::npos) {
-				i = length.find(" plus");
-				if (i != string::npos)
-					is_gluelength = true;
-			} else
-				is_gluelength = true;
-			// if yes transform "9xx minus 8yy plus 7zz"
-			// to "9xx-8yy+7zz"
-			if (is_gluelength) {
-				i = gluelength.find(" minus");
-				if (i != string::npos)
-					gluelength.replace(i, 7, "-");
-				i = gluelength.find(" plus");
-				if (i != string::npos)
-					gluelength.replace(i, 6, "+");
-			}
+			bool is_gluelength = is_glue_length(gluelength);
 
 			if (t.cs()[0] == 'h' && (known_unit || known_hspace || is_gluelength)) {
 				// Literal horizontal length or known variable

src/version.h

@@ -32,8 +32,8 @@ extern char const * const lyx_version_info;
 
 // Do not remove the comment below, so we get merge conflict in
 // independent branches. Instead add your own.
-#define LYX_FORMAT_LYX 621 // spitz: handle #% in frame urls
-#define LYX_FORMAT_TEX2LYX 621
+#define LYX_FORMAT_LYX 622 // spitz: support glue length in parskip
+#define LYX_FORMAT_TEX2LYX 622
 
 #if LYX_FORMAT_TEX2LYX != LYX_FORMAT_LYX
 #ifndef _MSC_VER