\s*
metadata-file-value
'
+ - []
+---
+
+The document's front matter wins over its `metadata-files` for a value both define, and what only the metadata file defines is kept, including entries of a list and keys of a mapping the front matter also defines.
+
+::: {#shared}
+{{< meta shared >}}
+:::
+
+::: {#custom-shared}
+{{< meta custom.shared >}}
+:::
+
+::: {#custom-from-document}
+{{< meta custom.from-document >}}
+:::
+
+::: {#custom-from-metadata-file}
+{{< meta custom.from-metadata-file >}}
+:::
diff --git a/tests/docs/smoke-all/metadata-merge/revealjs-controls-auto.qmd b/tests/docs/smoke-all/metadata-merge/revealjs-controls-auto.qmd
new file mode 100644
index 00000000000..6158e2cc9fe
--- /dev/null
+++ b/tests/docs/smoke-all/metadata-merge/revealjs-controls-auto.qmd
@@ -0,0 +1,22 @@
+---
+title: Controls and preview links set to auto
+format: revealjs
+controls: auto
+previewLinks: auto
+_quarto:
+ tests:
+ revealjs:
+ ensureFileRegexMatches:
+ -
+ - 'controls: false,'
+ - "'controlsAuto': true,"
+ - 'previewLinks: false,'
+ - "'previewLinksAuto': true,"
+ -
+ - 'controls: auto,'
+ - 'previewLinks: auto,'
+---
+
+## Slide
+
+`auto` is not a valid reveal.js value: Quarto passes `false` to reveal.js and enables its own automatic behavior instead.
diff --git a/tests/docs/smoke-all/metadata-merge/revealjs-controls-boolean-extra.yml b/tests/docs/smoke-all/metadata-merge/revealjs-controls-boolean-extra.yml
new file mode 100644
index 00000000000..f6118275244
--- /dev/null
+++ b/tests/docs/smoke-all/metadata-merge/revealjs-controls-boolean-extra.yml
@@ -0,0 +1,2 @@
+controls: true
+previewLinks: true
diff --git a/tests/docs/smoke-all/metadata-merge/revealjs-controls-boolean.qmd b/tests/docs/smoke-all/metadata-merge/revealjs-controls-boolean.qmd
new file mode 100644
index 00000000000..3e75b5e844b
--- /dev/null
+++ b/tests/docs/smoke-all/metadata-merge/revealjs-controls-boolean.qmd
@@ -0,0 +1,22 @@
+---
+title: Controls and preview links set in front matter and metadata-files
+format: revealjs
+metadata-files:
+ - revealjs-controls-boolean-extra.yml
+controls: false
+previewLinks: false
+_quarto:
+ tests:
+ revealjs:
+ ensureFileRegexMatches:
+ -
+ - 'controls: false,'
+ - 'previewLinks: false,'
+ -
+ - 'controls: true,'
+ - 'previewLinks: true,'
+---
+
+## Slide
+
+A boolean `controls` or `previewLinks` in the front matter wins over its `metadata-files`, like any other key.
diff --git a/tests/docs/smoke-all/metadata-merge/website-categories/.gitignore b/tests/docs/smoke-all/metadata-merge/website-categories/.gitignore
new file mode 100644
index 00000000000..812977e5f74
--- /dev/null
+++ b/tests/docs/smoke-all/metadata-merge/website-categories/.gitignore
@@ -0,0 +1,4 @@
+/.quarto/
+_site/
+
+**/*.quarto_ipynb
diff --git a/tests/docs/smoke-all/metadata-merge/website-categories/_quarto.yml b/tests/docs/smoke-all/metadata-merge/website-categories/_quarto.yml
new file mode 100644
index 00000000000..b0ae96b01d0
--- /dev/null
+++ b/tests/docs/smoke-all/metadata-merge/website-categories/_quarto.yml
@@ -0,0 +1,8 @@
+project:
+ type: website
+
+website:
+ title: "metadata-merge categories"
+
+categories:
+ - from-project
diff --git a/tests/docs/smoke-all/metadata-merge/website-categories/index.qmd b/tests/docs/smoke-all/metadata-merge/website-categories/index.qmd
new file mode 100644
index 00000000000..79c0997e309
--- /dev/null
+++ b/tests/docs/smoke-all/metadata-merge/website-categories/index.qmd
@@ -0,0 +1,5 @@
+---
+title: Website categories merge
+---
+
+Home page of the fixture. The assertions live in `posts/post.qmd`.
diff --git a/tests/docs/smoke-all/metadata-merge/website-categories/posts/_metadata.yml b/tests/docs/smoke-all/metadata-merge/website-categories/posts/_metadata.yml
new file mode 100644
index 00000000000..9b26cbfdc26
--- /dev/null
+++ b/tests/docs/smoke-all/metadata-merge/website-categories/posts/_metadata.yml
@@ -0,0 +1,4 @@
+author:
+ - name: from-directory
+categories:
+ - from-directory
diff --git a/tests/docs/smoke-all/metadata-merge/website-categories/posts/post.qmd b/tests/docs/smoke-all/metadata-merge/website-categories/posts/post.qmd
new file mode 100644
index 00000000000..61b185cefdd
--- /dev/null
+++ b/tests/docs/smoke-all/metadata-merge/website-categories/posts/post.qmd
@@ -0,0 +1,19 @@
+---
+title: A post
+author: from-document
+categories:
+ - from-document
+_quarto:
+ tests:
+ html:
+ ensureFileRegexMatches:
+ -
+ - 'class="quarto-category">from-project<'
+ - 'class="quarto-category">from-directory<'
+ - 'class="quarto-category">from-document<'
+ - '
'
+ - '
'
+ - []
+---
+
+In a website, `categories` from `_quarto.yml`, the directory `_metadata.yml` and the document front matter are all shown on the page. The `author` from the directory `_metadata.yml` and from the document front matter are both emitted too.
diff --git a/tests/smoke/project/project-metadata-merge.test.ts b/tests/smoke/project/project-metadata-merge.test.ts
new file mode 100644
index 00000000000..e5439e55422
--- /dev/null
+++ b/tests/smoke/project/project-metadata-merge.test.ts
@@ -0,0 +1,64 @@
+/*
+ * project-metadata-merge.test.ts
+ *
+ * Copyright (C) 2026 Posit Software, PBC
+ */
+import { existsSync } from "../../../src/deno_ral/fs.ts";
+import { join } from "../../../src/deno_ral/path.ts";
+
+import { testQuartoCmd } from "../../test.ts";
+import { docs } from "../../utils.ts";
+
+import { ensureFileRegexMatches, noErrorsOrWarnings } from "../../verify.ts";
+
+const projectDir = docs("project/metadata-merge");
+
+// keys defined in both _quarto.yml and the front matter are merged: the
+// document wins shared leaves, the project's other leaves and list entries stay
+const mergedKeys = [
+ /KEYWORDS: \[project-keyword, shared-keyword, document-keyword\]/,
+ /PARAMS: \[project-value\] \[document-value\]/,
+ /FROM-PROJECT: \[project-value\]/,
+ /SHARED: \[document-value\]/,
+ /FROM-DOCUMENT: \[document-value\]/,
+ /CUSTOM-LIST: \[project-item, document-item\]/,
+ /
\s*
project-value<\/p>/,
+];
+
+testQuartoCmd(
+ "render",
+ [projectDir, "--to", "html"],
+ [
+ noErrorsOrWarnings,
+ ensureFileRegexMatches(join(projectDir, "markdown.html"), mergedKeys),
+ ensureFileRegexMatches(
+ join(projectDir, "knitr.html"),
+ [
+ ...mergedKeys,
+ // a key holding an inline expression takes the executed value as a
+ // whole, without repeating a value the project also lists
+ /TAGS: \[project-tag, document-tag\]/,
+ /EVALUATED: \[evaluated-value\]/,
+ ],
+ [/`\{r\}/],
+ ),
+ ],
+ {
+ teardown: () => {
+ for (
+ const file of [
+ "markdown.html",
+ "markdown_files",
+ "knitr.html",
+ "knitr_files",
+ ]
+ ) {
+ const path = join(projectDir, file);
+ if (existsSync(path)) {
+ Deno.removeSync(path, { recursive: true });
+ }
+ }
+ return Promise.resolve();
+ },
+ },
+);
diff --git a/tests/smoke/render/render-cli-metadata-file.test.ts b/tests/smoke/render/render-cli-metadata-file.test.ts
new file mode 100644
index 00000000000..1e9075b4d44
--- /dev/null
+++ b/tests/smoke/render/render-cli-metadata-file.test.ts
@@ -0,0 +1,50 @@
+/*
+ * render-cli-metadata-file.test.ts
+ *
+ * Copyright (C) 2026 Posit Software, PBC
+ */
+import { existsSync } from "../../../src/deno_ral/fs.ts";
+import { join } from "../../../src/deno_ral/path.ts";
+
+import { testQuartoCmd } from "../../test.ts";
+import { docs } from "../../utils.ts";
+
+import { ensureFileRegexMatches, noErrorsOrWarnings } from "../../verify.ts";
+
+const dir = docs("metadata-merge-cli");
+const input = join(dir, "cli-metadata-file.qmd");
+const output = join(dir, "cli-metadata-file.html");
+
+// the document's front matter wins over a --metadata-file for a value both
+// define, and what only the metadata file defines is kept
+testQuartoCmd(
+ "render",
+ [
+ input,
+ "--to",
+ "html",
+ "--metadata-file",
+ join(dir, "cli-metadata-file.yml"),
+ ],
+ [
+ noErrorsOrWarnings,
+ ensureFileRegexMatches(output, [
+ //,
+ /
\s*
document-value<\/p>/,
+ /
\s*
document-value<\/p>/,
+ /
\s*
document-value<\/p>/,
+ /
\s*
metadata-file-value<\/p>/,
+ ]),
+ ],
+ {
+ teardown: () => {
+ for (const file of ["cli-metadata-file.html", "cli-metadata-file_files"]) {
+ const path = join(dir, file);
+ if (existsSync(path)) {
+ Deno.removeSync(path, { recursive: true });
+ }
+ }
+ return Promise.resolve();
+ },
+ },
+);
diff --git a/tests/smoke/render/render-freeze.test.ts b/tests/smoke/render/render-freeze.test.ts
index 82979a58444..4babf9ca3d6 100644
--- a/tests/smoke/render/render-freeze.test.ts
+++ b/tests/smoke/render/render-freeze.test.ts
@@ -12,7 +12,11 @@ import { Metadata } from "../../../src/config/types.ts";
import { removeIfEmptyDir, safeRemoveIfExists } from "../../../src/core/path.ts";
import { runQuarto } from "../../quarto-cmd.ts";
import { ExecuteOutput, Verify } from "../../test.ts";
-import { noErrors, outputCreated } from "../../verify.ts";
+import {
+ ensureHtmlElementContents,
+ noErrors,
+ outputCreated,
+} from "../../verify.ts";
import { testRender } from "./render.ts";
const regex = /output file: .*\.knit\.md/m;
@@ -185,3 +189,55 @@ testRender(
teardown: testContext.teardown,
},
);
+
+// Inline R expressions in YAML front matter stay evaluated when the render
+// reuses the frozen execution results instead of running knitr again
+const inlineYamlFileName = "freeze-inline-yaml";
+const inlineYamlDir = Deno.makeTempDirSync();
+const inlineYamlPath = join(inlineYamlDir, `${inlineYamlFileName}.qmd`);
+const inlineYamlContext = testFileContext(
+ inlineYamlPath,
+ {
+ title: "Title `r 1 + 1`",
+ "custom-key": "Custom `r 2 + 3`",
+ format: "html",
+ freeze: true,
+ },
+ [
+ "::: {#custom-key}",
+ "{{< meta custom-key >}}",
+ ":::",
+ "",
+ "```{r}",
+ "1 + 1",
+ "```",
+ "",
+ ],
+);
+testRender(
+ inlineYamlDir + "/",
+ "html",
+ false,
+ [
+ noErrors,
+ useFrozen,
+ ensureHtmlElementContents(
+ join(inlineYamlDir, `${inlineYamlFileName}.html`),
+ { selectors: ["h1.title"], matches: [/^\s*Title 2\s*$/] },
+ ),
+ ensureHtmlElementContents(
+ join(inlineYamlDir, `${inlineYamlFileName}.html`),
+ { selectors: ["#custom-key"], matches: [/^\s*Custom 5\s*$/] },
+ ),
+ ],
+ {
+ name: "frozen inline R in YAML",
+ setup: inlineYamlContext.setup,
+ teardown: async () => {
+ await inlineYamlContext.teardown();
+ const freezerDir = join(inlineYamlDir, "_freeze");
+ safeRemoveIfExists(join(freezerDir, inlineYamlFileName));
+ removeIfEmptyDir(freezerDir);
+ },
+ },
+);