diff --git a/test/README.md b/test/README.md
index 2469ce68f5..b049946d2e 100644
--- a/test/README.md
+++ b/test/README.md
@@ -3,7 +3,12 @@ and are here relicensed by their original author (Eemeli Aro) under the Unicode
 
 These test files are intended to be useful for testing multiple different message processors in different ways:
 
-- `syntax-errors.json` — An array of strings that should produce a Syntax Error or a Data Model Error when parsed.
+- `syntax-errors.json` — An array of strings that should produce a Syntax Error when parsed.
+
+- `data-model-errors.json` - An object with string keys and arrays of strings as values,
+     where each key is the name of an error and its value is array of strings that
+     should produce `error` when processed.
+     Error names are defined in ["MessageFormat 2.0 Errors"](../spec/errors.md) in the spec.
 
 - `test-core.json` — An array of test cases that do not depend on any registry definitions.
   Each test may include some of the following fields:
diff --git a/test/data-model-errors.json b/test/data-model-errors.json
new file mode 100644
index 0000000000..3c7f1c9b88
--- /dev/null
+++ b/test/data-model-errors.json
@@ -0,0 +1,32 @@
+[
+    "Variant Key Mismatch": [
+        ".match {$foo :x} * * {{foo}}",
+        ".match {$foo :x} {$bar :x} * {{foo}}"
+    ],
+    "Missing Fallback Variant": [
+        ".match {:foo} 1 {{_}}",
+        ".match {:foo} other {{_}}",
+        ".match {:foo} {:bar} * 1 {{_}} 1 * {{_}}"
+    ],
+    "Missing Selector Annotation": [
+        ".match {$foo} one {{one}} * {{other}}",
+        ".input {$foo} .match {$foo} one {{one}} * {{other}}",
+        ".local $foo = {$bar} .match {$foo} one {{one}} * {{other}}"
+    ],
+    "Duplicate Declaration": [
+        ".input {$foo} .input {$foo} {{_}}",
+        ".input {$foo} .local $foo = {42} {{_}}",
+        ".local $foo = {42} .input {$foo} {{_}}",
+        ".local $foo = {:unknown} .local $foo = {42} {{_}}",
+        ".local $foo = {$bar} .local $bar = {42} {{_}}",
+        ".local $foo = {$foo} {{_}}",
+        ".local $foo = {$bar} .local $bar = {$baz} {{_}}",
+        ".local $foo = {$bar :func} .local $bar = {$baz} {{_}}",
+        ".local $foo = {42 :func opt=$foo} {{_}}",
+        ".local $foo = {42 :func opt=$bar} .local $bar = {42} {{_}}",
+    ],
+    "Duplicate Option Name": [
+            "bad {:placeholder option=x option=x}",
+            "bad {:placeholder ns:option=x ns:option=y}"
+    ]
+]
diff --git a/test/syntax-errors.json b/test/syntax-errors.json
index c607e632e8..2d73b83961 100644
--- a/test/syntax-errors.json
+++ b/test/syntax-errors.json
@@ -20,8 +20,6 @@
   "bad {:} placeholder",
   "bad {\\u0000placeholder}",
   "no-equal {|42| :number minimumFractionDigits 2}",
-  "bad {:placeholder option=x option=x}",
-  "bad {:placeholder ns:option=x ns:option=y}",
   "bad {:placeholder option=}",
   "bad {:placeholder option value}",
   "bad {:placeholder option:value}",
@@ -41,33 +39,15 @@
   "no {|placeholder| end",
   "no {|literal} end",
   "no {|literal or placeholder end",
-  ".input {$foo} .input {$foo} {{_}}",
-  ".input {$foo} .local $foo = {42} {{_}}",
-  ".local $foo = {42} .input {$foo} {{_}}",
-  ".local $foo = {:unknown} .local $foo = {42} {{_}}",
   ".local bar = {|foo|} {{_}}",
   ".local #bar = {|foo|} {{_}}",
   ".local $bar {|foo|} {{_}}",
   ".local $bar = |foo| {{_}}",
-  ".local $foo = {$bar} .local $bar = {42} {{_}}",
-  ".local $foo = {$foo} {{_}}",
-  ".local $foo = {$bar} .local $bar = {$baz} {{_}}",
-  ".local $foo = {$bar :func} .local $bar = {$baz} {{_}}",
-  ".local $foo = {42 :func opt=$foo} {{_}}",
-  ".local $foo = {42 :func opt=$bar} .local $bar = {42} {{_}}",
   ".match {#foo} * {{foo}}",
   ".match {} * {{foo}}",
   ".match {|foo| :x} {|bar| :x} ** {{foo}}",
   ".match * {{foo}}",
   ".match {|x| :x} * foo",
   ".match {|x| :x} * {{foo}} extra",
-  ".match |x| * {{foo}}",
-  ".match {:foo} 1 {{_}}",
-  ".match {:foo} other {{_}}",
-  ".match {:foo} {:bar} * 1 {{_}} 1 * {{_}}",
-  ".match {$foo :x} * * {{foo}}",
-  ".match {$foo :x} {$bar :x} * {{foo}}",
-  ".match {$foo} one {{one}} * {{other}}",
-  ".input {$foo} .match {$foo} one {{one}} * {{other}}",
-  ".local $foo = {$bar} .match {$foo} one {{one}} * {{other}}"
+  ".match |x| * {{foo}}"
 ]