cli: apply theme to pdf exports

ci/release/changelogs/next.md

@@ -10,6 +10,7 @@
 
 #### Bugfixes ⛑️
 
+- Theme flags on CLI apply to PDFs [#1894](https://github.com/terrastruct/d2/pull/1894)
 - Fixes styles in connections not overriding styles set by globs [#1857](https://github.com/terrastruct/d2/pull/1857)
 - Fixes `null` being set on a nested shape not working in certain cases when connections also pointed to that shape [#1830](https://github.com/terrastruct/d2/pull/1830)
 - Fixes edge case of bad import syntax crashing using d2 as a library [#1829](https://github.com/terrastruct/d2/pull/1829)

d2cli/main.go

@@ -936,10 +936,11 @@ func renderPDF(ctx context.Context, ms *xmain.State, plugin d2plugin.Plugin, opt
 		}
 
 		svg, err = d2svg.Render(diagram, &d2svg.RenderOpts{
-			Pad:    opts.Pad,
-			Sketch: opts.Sketch,
-			Center: opts.Center,
-			Scale:  scale,
+			Pad:     opts.Pad,
+			Sketch:  opts.Sketch,
+			Center:  opts.Center,
+			Scale:   scale,
+			ThemeID: opts.ThemeID,
 		})
 		if err != nil {
 			return nil, err

e2etests-cli/main_test.go

@@ -765,6 +765,18 @@ i used to read
 				assert.Testdata(t, ".svg", svg)
 			},
 		},
+		{
+			name:   "theme-pdf",
+			skipCI: true,
+			run: func(t *testing.T, ctx context.Context, dir string, env *xos.Env) {
+				writeFile(t, dir, "in.d2", `x -> y`)
+				err := runTestMain(t, ctx, dir, env, "--theme=5", "in.d2", "out.pdf")
+				assert.Success(t, err)
+
+				pdf := readFile(t, dir, "out.pdf")
+				testdataIgnoreDiff(t, ".pdf", pdf)
+			},
+		},
 		{
 			name:   "renamed-board",
 			skipCI: true,