Merge pull request #2232 from alixander/bad-latex

d2parser: escape backslashes for latex

ci/release/changelogs/next.md

@@ -7,6 +7,9 @@
 
 - Composition: links pointing to own board are purged [#2203](https://github.com/terrastruct/d2/pull/2203)
 - Syntax: reserved keywords must be unquoted [#2231](https://github.com/terrastruct/d2/pull/2231)
+- Latex: Backslashes in Latex blocks do not escape [#2232](https://github.com/terrastruct/d2/pull/2232)
+  - This is a breaking change. Previously Latex blocks required escaping the backslash. So
+    for older D2 versions, you should remove the excess backslashes.
 
 #### Bugfixes ⛑️
 

d2parser/parse.go

@@ -1480,6 +1480,12 @@ func (p *parser) parseBlockString() *d2ast.BlockString {
 		}
 
 		if r != endHint {
+			if (bs.Tag == "latex" || bs.Tag == "tex") && r == '\\' {
+				// For LaTeX, where single backslash is common, we escape it so that users don't have to write double the backslashes
+				sb.WriteRune('\\')
+				sb.WriteRune('\\')
+				continue
+			}
 			sb.WriteRune(r)
 			continue
 		}

e2etests/stable_test.go

@@ -1381,30 +1381,24 @@ c: |md
 		{
 			name: "latex",
 			script: `a: |latex
-\\Huge{\\frac{\\alpha g^2}{\\omega^5} e^{[ -0.74\\bigl\\{\\frac{\\omega U_\\omega 19.5}{g}\\bigr\\}^{\\!-4}\\,]}}
+\Huge{\frac{\alpha g^2}{\omega^5} e^{[ -0.74\bigl\{\frac{\omega U_\omega 19.5}{g}\bigr\}^{\!-4}\,]}}
 |
-
 b: |latex
 e = mc^2
 |
-
 z: |latex
-gibberish\\; math:\\sum_{i=0}^\\infty i^2
+gibberish\; math:\sum_{i=0}^\infty i^2
 |
-
 z -> a
 z -> b
-
 a -> c
 b -> c
 sugar -> c
 c: mixed together
-
 c -> solution: we get
-
 Linear program: {
   formula: |latex
-    \\min_{ \\mathclap{\\substack{ x \\in \\mathbb{R}^n \\ x \\geq 0 \\ Ax \\leq b }}} c^T x
+    \min_{ \mathclap{\substack{ x \in \mathbb{R}^n \ x \geq 0 \ Ax \leq b }}} c^T x
   |
 }
 `,

e2etests/testdata/files/grid_outside_labels.d2

@@ -4,61 +4,55 @@ container: ___________________________________container_________________________
 
   amscd plugin: {
     ex: |tex
-      \\begin{CD} B @>{\\text{very long label}}>> C S^{{\\mathcal{W}}_\\Lambda}\\otimes T @>j>> T\\\\ @VVV V \\end{CD}
+      \begin{CD} B @>{\text{very long label}}>> C S^{{\mathcal{W}}_\Lambda}\otimes T @>j>> T\\ @VVV V \end{CD}
     |
   }
 
   braket plugin: {
     style.3d: true
     ex: |tex
-      \\bra{a}\\ket{b}
+      \bra{a}\ket{b}
     |
   }
 
   cancel plugin: {
     ex: |tex
-      \\cancel{Culture + 5}
+      \cancel{Culture + 5}
     |
   }
-
   color plugin: {
     icon: https://icons.terrastruct.com/essentials/profits.svg
     icon.near: outside-right-center
     ex: |tex
-      \\textcolor{red}{y} = \\textcolor{green}{\\sin} x
+      \textcolor{red}{y} = \textcolor{green}{\sin} x
     |
   }
-
   gensymb plugin: {
     ex: |tex
-      \\lambda = 10.6\\,\\micro\\mathrm{m}
+      \lambda = 10.6\,\micro\mathrm{m}
     |
   }
-
   mhchem plugin: {
     style.multiple: true
     ex: |tex
       \ce{SO4^2- + Ba^2+ -> BaSO4 v}
     |
   }
-
   physics plugin: {
     ex: |tex
-      \\var{F[g(x)]}
+      \var{F[g(x)]}
-      \\dd(\\cos\\theta)
+      \dd(\cos\theta)
     |
   }
-
   multilines: {
     ex: |tex
-      \\displaylines{x = a + b \\\\ y = b + c}
+      \displaylines{x = a + b \\ y = b + c}
-      \\sum_{k=1}^{n} h_{k} \\int_{0}^{1} \\bigl(\\partial_{k} f(x_{k-1}+t h_{k} e_{k}) -\\partial_{k} f(a)\\bigr) \\,dt
+      \sum_{k=1}^{n} h_{k} \int_{0}^{1} \bigl(\partial_{k} f(x_{k-1}+t h_{k} e_{k}) -\partial_{k} f(a)\bigr) \,dt
     |
   }
-
   asm: {
     ex: |latex
-      \\min_{ \\mathclap{\\substack{ x \\in \\mathbb{R}^n \\ x \\geq 0 \\ Ax \\leq b }}} c^T x
+      \min_{ \mathclap{\substack{ x \in \mathbb{R}^n \ x \geq 0 \ Ax \leq b }}} c^T x
     |
   }
 }

e2etests/testdata/files/grid_with_latex.d2

@@ -19,7 +19,7 @@ y: {
 z: {
   grid-columns: 2
   lim: |latex
-    \\lim_{h \\rightarrow 0 } \\frac{f(x+h)-f(x)}{h}
+    \lim_{h \rightarrow 0 } \frac{f(x+h)-f(x)}{h}
   |
   add: |latex
     1 + 1

e2etests/testdata/stable/grid_outside_labels/dagre/board.exp.json

@@ -10,7 +10,7 @@
         "x": 0,
         "y": 0
       },
-      "width": 1213,
+      "width": 1184,
       "height": 524,
       "opacity": 1,
       "strokeDash": 0,
@@ -294,7 +294,7 @@
         "x": 385,
         "y": 82
       },
-      "width": 255,
+      "width": 226,
       "height": 103,
       "opacity": 1,
       "strokeDash": 0,
@@ -387,7 +387,7 @@
         "x": 385,
         "y": 241
       },
-      "width": 324,
+      "width": 295,
       "height": 103,
       "opacity": 1,
       "strokeDash": 0,
@@ -468,7 +468,7 @@
         "x": 385,
         "y": 410
       },
-      "width": 314,
+      "width": 285,
       "height": 93,
       "opacity": 1,
       "strokeDash": 0,
@@ -509,8 +509,8 @@
         "x": 415,
         "y": 440
       },
-      "width": 254,
+      "width": 225,
-      "height": 18,
+      "height": 20,
       "opacity": 1,
       "strokeDash": 0,
       "strokeWidth": 2,
@@ -529,7 +529,7 @@
       "fields": null,
       "methods": null,
       "columns": null,
-      "label": "\\ce{SO4^2- + Ba^2+ -> BaSO4 v}",
+      "label": "\\\\ce{SO4^2- + Ba^2+ -> BaSO4 v}",
       "fontSize": 16,
       "fontFamily": "DEFAULT",
       "language": "latex",
@@ -537,8 +537,8 @@
       "italic": false,
       "bold": false,
       "underline": false,
-      "labelWidth": 254,
+      "labelWidth": 225,
-      "labelHeight": 18,
+      "labelHeight": 20,
       "zIndex": 0,
       "level": 3
     },
@@ -546,7 +546,7 @@
       "id": "container.physics plugin",
       "type": "rectangle",
       "pos": {
-        "x": 729,
+        "x": 700,
         "y": 82
       },
       "width": 464,
@@ -587,7 +587,7 @@
       "id": "container.physics plugin.ex",
       "type": "text",
       "pos": {
-        "x": 759,
+        "x": 730,
         "y": 112
       },
       "width": 128,
@@ -627,7 +627,7 @@
       "id": "container.multilines",
       "type": "rectangle",
       "pos": {
-        "x": 729,
+        "x": 700,
         "y": 233
       },
       "width": 464,
@@ -668,7 +668,7 @@
       "id": "container.multilines.ex",
       "type": "text",
       "pos": {
-        "x": 759,
+        "x": 730,
         "y": 263
       },
       "width": 404,
@@ -708,7 +708,7 @@
       "id": "container.asm",
       "type": "rectangle",
       "pos": {
-        "x": 729,
+        "x": 700,
         "y": 401
       },
       "width": 464,
@@ -749,7 +749,7 @@
       "id": "container.asm.ex",
       "type": "text",
       "pos": {
-        "x": 759,
+        "x": 730,
         "y": 431
       },
       "width": 62,

e2etests/testdata/stable/grid_outside_labels/elk/board.exp.json

@@ -10,7 +10,7 @@
         "x": 12,
         "y": 12
       },
-      "width": 1323,
+      "width": 1294,
       "height": 521,
       "opacity": 1,
       "strokeDash": 0,
@@ -294,7 +294,7 @@
         "x": 437,
         "y": 58
       },
-      "width": 285,
+      "width": 256,
       "height": 148,
       "opacity": 1,
       "strokeDash": 0,
@@ -387,7 +387,7 @@
         "x": 437,
         "y": 226
       },
-      "width": 354,
+      "width": 325,
       "height": 133,
       "opacity": 1,
       "strokeDash": 0,
@@ -468,8 +468,8 @@
         "x": 437,
         "y": 389
       },
-      "width": 344,
+      "width": 315,
-      "height": 123,
+      "height": 124,
       "opacity": 1,
       "strokeDash": 0,
       "strokeWidth": 2,
@@ -509,8 +509,8 @@
         "x": 482,
         "y": 434
       },
-      "width": 254,
+      "width": 225,
-      "height": 18,
+      "height": 20,
       "opacity": 1,
       "strokeDash": 0,
       "strokeWidth": 2,
@@ -529,7 +529,7 @@
       "fields": null,
       "methods": null,
       "columns": null,
-      "label": "\\ce{SO4^2- + Ba^2+ -> BaSO4 v}",
+      "label": "\\\\ce{SO4^2- + Ba^2+ -> BaSO4 v}",
       "fontSize": 16,
       "fontFamily": "DEFAULT",
       "language": "latex",
@@ -537,8 +537,8 @@
       "italic": false,
       "bold": false,
       "underline": false,
-      "labelWidth": 254,
+      "labelWidth": 225,
-      "labelHeight": 18,
+      "labelHeight": 20,
       "zIndex": 0,
       "level": 3
     },
@@ -546,7 +546,7 @@
       "id": "container.physics plugin",
       "type": "rectangle",
       "pos": {
-        "x": 811,
+        "x": 782,
         "y": 58
       },
       "width": 504,
@@ -587,7 +587,7 @@
       "id": "container.physics plugin.ex",
       "type": "text",
       "pos": {
-        "x": 861,
+        "x": 832,
         "y": 108
       },
       "width": 128,
@@ -627,7 +627,7 @@
       "id": "container.multilines",
       "type": "rectangle",
       "pos": {
-        "x": 811,
+        "x": 782,
         "y": 204
       },
       "width": 504,
@@ -668,7 +668,7 @@
       "id": "container.multilines.ex",
       "type": "text",
       "pos": {
-        "x": 861,
+        "x": 832,
         "y": 254
       },
       "width": 404,
@@ -708,7 +708,7 @@
       "id": "container.asm",
       "type": "rectangle",
       "pos": {
-        "x": 811,
+        "x": 782,
         "y": 376
       },
       "width": 504,
@@ -749,7 +749,7 @@
       "id": "container.asm.ex",
       "type": "text",
       "pos": {
-        "x": 861,
+        "x": 832,
         "y": 426
       },
       "width": 62,

e2etests/testdata/txtar/single-backslash-latex/dagre/board.exp.json

@@ -0,0 +1,129 @@
+{
+  "name": "",
+  "isFolderOnly": false,
+  "fontFamily": "SourceSansPro",
+  "shapes": [
+    {
+      "id": "formula",
+      "type": "rectangle",
+      "pos": {
+        "x": 10,
+        "y": 20
+      },
+      "width": 142,
+      "height": 142,
+      "opacity": 1,
+      "strokeDash": 0,
+      "strokeWidth": 2,
+      "borderRadius": 0,
+      "fill": "B4",
+      "stroke": "B1",
+      "shadow": false,
+      "3d": false,
+      "multiple": false,
+      "double-border": false,
+      "tooltip": "",
+      "link": "",
+      "icon": null,
+      "iconPosition": "",
+      "blend": false,
+      "fields": null,
+      "methods": null,
+      "columns": null,
+      "label": "formula",
+      "fontSize": 28,
+      "fontFamily": "DEFAULT",
+      "language": "",
+      "color": "N1",
+      "italic": false,
+      "bold": false,
+      "underline": false,
+      "labelWidth": 92,
+      "labelHeight": 36,
+      "labelPosition": "OUTSIDE_TOP_CENTER",
+      "zIndex": 0,
+      "level": 1
+    },
+    {
+      "id": "formula.equation",
+      "type": "text",
+      "pos": {
+        "x": 40,
+        "y": 50
+      },
+      "width": 82,
+      "height": 82,
+      "opacity": 1,
+      "strokeDash": 0,
+      "strokeWidth": 2,
+      "borderRadius": 0,
+      "fill": "transparent",
+      "stroke": "N1",
+      "shadow": false,
+      "3d": false,
+      "multiple": false,
+      "double-border": false,
+      "tooltip": "",
+      "link": "",
+      "icon": null,
+      "iconPosition": "",
+      "blend": false,
+      "fields": null,
+      "methods": null,
+      "columns": null,
+      "label": "\\\\begin{equation} \\\\label{eq1}\n\\\\begin{split}\nA & = \\\\frac{\\\\\\\\pi r^2}{2} \\\\\\\\\n & = \\\\frac{1}{2} \\\\pi r^2\n\\\\end{split}\n\\\\end{equation}",
+      "fontSize": 16,
+      "fontFamily": "DEFAULT",
+      "language": "latex",
+      "color": "N1",
+      "italic": false,
+      "bold": false,
+      "underline": false,
+      "labelWidth": 82,
+      "labelHeight": 82,
+      "zIndex": 0,
+      "level": 2
+    }
+  ],
+  "connections": [],
+  "root": {
+    "id": "",
+    "type": "",
+    "pos": {
+      "x": 0,
+      "y": 0
+    },
+    "width": 0,
+    "height": 0,
+    "opacity": 0,
+    "strokeDash": 0,
+    "strokeWidth": 0,
+    "borderRadius": 0,
+    "fill": "N7",
+    "stroke": "",
+    "shadow": false,
+    "3d": false,
+    "multiple": false,
+    "double-border": false,
+    "tooltip": "",
+    "link": "",
+    "icon": null,
+    "iconPosition": "",
+    "blend": false,
+    "fields": null,
+    "methods": null,
+    "columns": null,
+    "label": "",
+    "fontSize": 0,
+    "fontFamily": "",
+    "language": "",
+    "color": "",
+    "italic": false,
+    "bold": false,
+    "underline": false,
+    "labelWidth": 0,
+    "labelHeight": 0,
+    "zIndex": 0,
+    "level": 0
+  }
+}

e2etests/testdata/txtar/single-backslash-latex/elk/board.exp.json

@@ -0,0 +1,129 @@
+{
+  "name": "",
+  "isFolderOnly": false,
+  "fontFamily": "SourceSansPro",
+  "shapes": [
+    {
+      "id": "formula",
+      "type": "rectangle",
+      "pos": {
+        "x": 12,
+        "y": 12
+      },
+      "width": 182,
+      "height": 182,
+      "opacity": 1,
+      "strokeDash": 0,
+      "strokeWidth": 2,
+      "borderRadius": 0,
+      "fill": "B4",
+      "stroke": "B1",
+      "shadow": false,
+      "3d": false,
+      "multiple": false,
+      "double-border": false,
+      "tooltip": "",
+      "link": "",
+      "icon": null,
+      "iconPosition": "",
+      "blend": false,
+      "fields": null,
+      "methods": null,
+      "columns": null,
+      "label": "formula",
+      "fontSize": 28,
+      "fontFamily": "DEFAULT",
+      "language": "",
+      "color": "N1",
+      "italic": false,
+      "bold": false,
+      "underline": false,
+      "labelWidth": 92,
+      "labelHeight": 36,
+      "labelPosition": "INSIDE_TOP_CENTER",
+      "zIndex": 0,
+      "level": 1
+    },
+    {
+      "id": "formula.equation",
+      "type": "text",
+      "pos": {
+        "x": 62,
+        "y": 62
+      },
+      "width": 82,
+      "height": 82,
+      "opacity": 1,
+      "strokeDash": 0,
+      "strokeWidth": 2,
+      "borderRadius": 0,
+      "fill": "transparent",
+      "stroke": "N1",
+      "shadow": false,
+      "3d": false,
+      "multiple": false,
+      "double-border": false,
+      "tooltip": "",
+      "link": "",
+      "icon": null,
+      "iconPosition": "",
+      "blend": false,
+      "fields": null,
+      "methods": null,
+      "columns": null,
+      "label": "\\\\begin{equation} \\\\label{eq1}\n\\\\begin{split}\nA & = \\\\frac{\\\\\\\\pi r^2}{2} \\\\\\\\\n & = \\\\frac{1}{2} \\\\pi r^2\n\\\\end{split}\n\\\\end{equation}",
+      "fontSize": 16,
+      "fontFamily": "DEFAULT",
+      "language": "latex",
+      "color": "N1",
+      "italic": false,
+      "bold": false,
+      "underline": false,
+      "labelWidth": 82,
+      "labelHeight": 82,
+      "zIndex": 0,
+      "level": 2
+    }
+  ],
+  "connections": [],
+  "root": {
+    "id": "",
+    "type": "",
+    "pos": {
+      "x": 0,
+      "y": 0
+    },
+    "width": 0,
+    "height": 0,
+    "opacity": 0,
+    "strokeDash": 0,
+    "strokeWidth": 0,
+    "borderRadius": 0,
+    "fill": "N7",
+    "stroke": "",
+    "shadow": false,
+    "3d": false,
+    "multiple": false,
+    "double-border": false,
+    "tooltip": "",
+    "link": "",
+    "icon": null,
+    "iconPosition": "",
+    "blend": false,
+    "fields": null,
+    "methods": null,
+    "columns": null,
+    "label": "",
+    "fontSize": 0,
+    "fontFamily": "",
+    "language": "",
+    "color": "",
+    "italic": false,
+    "bold": false,
+    "underline": false,
+    "labelWidth": 0,
+    "labelHeight": 0,
+    "zIndex": 0,
+    "level": 0
+  }
+}

e2etests/themes_test.go

@@ -111,8 +111,8 @@ func main() {
 
 markdown -> code -> ex
 ex: |tex
-	\\displaylines{x = a + b \\\\ y = b + c}
+	\displaylines{x = a + b \\ y = b + c}
-	\\sum_{k=1}^{n} h_{k} \\int_{0}^{1} \\bigl(\\partial_{k} f(x_{k-1}+t h_{k} e_{k}) -\\partial_{k} f(a)\\bigr) \\,dt
+	\sum_{k=1}^{n} h_{k} \int_{0}^{1} \bigl(\partial_{k} f(x_{k-1}+t h_{k} e_{k}) -\partial_{k} f(a)\bigr) \,dt
 |
 `,
 		},
@@ -218,8 +218,8 @@ func main() {
 
 markdown -> code -> ex
 ex: |tex
-	\\displaylines{x = a + b \\\\ y = b + c}
+	\displaylines{x = a + b \\ y = b + c}
-	\\sum_{k=1}^{n} h_{k} \\int_{0}^{1} \\bigl(\\partial_{k} f(x_{k-1}+t h_{k} e_{k}) -\\partial_{k} f(a)\\bigr) \\,dt
+	\sum_{k=1}^{n} h_{k} \int_{0}^{1} \bigl(\partial_{k} f(x_{k-1}+t h_{k} e_{k}) -\partial_{k} f(a)\bigr) \,dt
 |
 `,
 		},

e2etests/txtar.txt

@@ -657,3 +657,15 @@ my_table: {
 }
 
 x -> my_table."shape"
+
+-- single-backslash-latex --
+formula: {
+  equation: |latex
+    \begin{equation} \label{eq1}
+    \begin{split}
+    A & = \frac{\\pi r^2}{2} \\
+     & = \frac{1}{2} \pi r^2
+    \end{split}
+    \end{equation}
+  |
+}