feat: add tests for metadata transformations with substitutions

src/services/metadata/utils.ts

@@ -3,7 +3,8 @@ import {FileMetadata, serializeMetadata} from './parse';
 
 // IMO, we should just always apply this at the end of the whole processing pipeline,
 // not when dumping meta/front matter
-const normalizeLineEndings = (input: string): string => input.replace(/\r?\n/g, carriageReturn);
+export const normalizeLineEndings = (input: string): string =>
+    input.replace(/\r?\n/g, carriageReturn);
 
 export const emplaceMetadata = (metadataStrippedContent: string, metadata: FileMetadata) =>
     normalizeLineEndings(`${serializeMetadata(metadata)}${metadataStrippedContent}`);

tests/integrations/services/__snapshots__/liquidInFrontMatter.test.ts.snap

@@ -0,0 +1,49 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Front matter (metadata) transformations do not break when a property key contains Liquid-style variable substitutions 1`] = `
+{
+  "(({{ key-name }}))": "This one's key employs a different whitespace style in a substitution.",
+  "(({{key-name}}))": "This one's key only consists of a substitution.",
+  "(({{key-name}}))-prop": "This one's key starts with a substitution.",
+  "prop-(({{key-name}}))": "This one has a substitution in a key name.",
+}
+`;
+
+exports[`Front matter (metadata) transformations do not break when a property key contains Liquid-style variable substitutions 2`] = `
+"---
+prop-{{key-name}}: This one has a substitution in a key name.
+{{key-name}}-prop: This one's key starts with a substitution.
+{{key-name}}: This one's key only consists of a substitution.
+{{ key-name }}: This one's key employs a different whitespace style in a substitution.
+---
+Blah.
+"
+`;
+
+exports[`Front matter (metadata) transformations do not break when a property value contains Liquid-style variable substitutions 1`] = `
+{
+  "prop1": "This is a metadata property with a (({{substitution}})) in it.",
+  "prop2": "This one contains (({{multiple}})) (({{substitutions}})).",
+  "prop3": "This one has (({{substitutions}})) of (({{ different }})) (({{  styles}})).",
+  "prop4": "This one has a (({{substitution}})) as well, but the string literal is single-quoted.",
+  "prop5": "This one has no quotes at (({{all}})).",
+  "prop6": "(({{this}})) starts with a substitution.",
+  "prop7": "(({{this}})) one is a multiline (({{property}})).",
+}
+`;
+
+exports[`Front matter (metadata) transformations do not break when a property value contains Liquid-style variable substitutions 2`] = `
+"---
+prop1: This is a metadata property with a {{substitution}} in it.
+prop2: This one contains {{multiple}} {{substitutions}}.
+prop3: This one has {{substitutions}} of {{ different }} {{  styles}}.
+prop4: >-
+  This one has a {{substitution}} as well, but the string literal is
+  single-quoted.
+prop5: This one has no quotes at {{all}}.
+prop6: {{this}} starts with a substitution.
+prop7: {{this}} one is a multiline {{property}}.
+---
+Blah.
+"
+`;

tests/integrations/services/liquidInFrontMatter.test.ts

@@ -0,0 +1,28 @@
+import {readFile} from 'fs/promises';
+import {parseExistingMetadata} from 'services/metadata/parse';
+import {emplaceMetadata} from 'services/metadata/utils';
+
+const propValuesMockPath = 'mocks/fileContent/metadata/substitutionsInMetadataPropertyValues.md';
+const propKeysMockPath = 'mocks/fileContent/metadata/substitutionsInMetadataPropertyKeys.md';
+
+describe('Front matter (metadata) transformations', () => {
+    it('do not break when a property value contains Liquid-style variable substitutions', async () => {
+        const fileContent = await readFile(propValuesMockPath, {encoding: 'utf-8'});
+
+        const {metadata, metadataStrippedContent} = parseExistingMetadata(fileContent);
+        const processedContent = emplaceMetadata(metadataStrippedContent, metadata);
+
+        expect(metadata).toMatchSnapshot();
+        expect(processedContent).toMatchSnapshot();
+    });
+
+    it('do not break when a property key contains Liquid-style variable substitutions', async () => {
+        const fileContent = await readFile(propKeysMockPath, {encoding: 'utf-8'});
+
+        const {metadata, metadataStrippedContent} = parseExistingMetadata(fileContent);
+        const processedContent = emplaceMetadata(metadataStrippedContent, metadata);
+
+        expect(metadata).toMatchSnapshot();
+        expect(processedContent).toMatchSnapshot();
+    });
+});

tests/mocks/fileContent/metadata/substitutionsInMetadataPropertyKeys.md

@@ -0,0 +1,7 @@
+---
+prop-{{key-name}}: This one has a substitution in a key name.
+{{key-name}}-prop: This one's key starts with a substitution.
+{{key-name}}: This one's key only consists of a substitution.
+{{ key-name }}: This one's key employs a different whitespace style in a substitution.
+---
+Blah.

tests/mocks/fileContent/metadata/substitutionsInMetadataPropertyValues.md

@@ -0,0 +1,11 @@
+---
+prop1: "This is a metadata property with a {{substitution}} in it."
+prop2: "This one contains {{multiple}} {{substitutions}}."
+prop3: "This one has {{substitutions}} of {{ different }} {{  styles}}."
+prop4: 'This one has a {{substitution}} as well, but the string literal is single-quoted.'
+prop5: This one has no quotes at {{all}}.
+prop6: {{this}} starts with a substitution.
+prop7: >-
+  {{this}} one is a multiline {{property}}.
+---
+Blah.