feat: JSON5 support

Reference: https://spec.json5.org/
Co-authored-by: Codex <codex@openai.com>
Generated-with: OpenAI Codex CLI (partial)
Signed-off-by: Robin H. Johnson <rjohnson@coreweave.com>

Author: robbat2

README.md

@@ -415,7 +415,7 @@ Flags:
   -h, --help                            help for yq
   -I, --indent int                      sets indent level for output (default 2)
   -i, --inplace                         update the file in place of first file given.
-  -p, --input-format string             [auto|a|yaml|y|json|j|kyaml|ky|props|p|csv|c|tsv|t|xml|x|base64|uri|toml|hcl|h|lua|l|ini|i] parse format for input. (default "auto")
+  -p, --input-format string             [auto|a|yaml|y|json|j|json5|j5|kyaml|ky|props|p|csv|c|tsv|t|xml|x|base64|uri|toml|hcl|h|lua|l|ini|i] parse format for input. (default "auto")
       --lua-globals                     output keys as top-level global variables
       --lua-prefix string               prefix (default "return ")
       --lua-suffix string               suffix (default ";\n")
@@ -424,7 +424,7 @@ Flags:
   -N, --no-doc                          Don't print document separators (---)
   -0, --nul-output                      Use NUL char to separate values. If unwrap scalar is also set, fail if unwrapped scalar contains NUL char.
   -n, --null-input                      Don't read input, simply evaluate the expression given. Useful for creating docs from scratch.
-  -o, --output-format string            [auto|a|yaml|y|json|j|kyaml|ky|props|p|csv|c|tsv|t|xml|x|base64|uri|toml|hcl|h|shell|s|lua|l|ini|i] output format type. (default "auto")
+  -o, --output-format string            [auto|a|yaml|y|json|j|json5|j5|kyaml|ky|props|p|csv|c|tsv|t|xml|x|base64|uri|toml|hcl|h|shell|s|lua|l|ini|i] output format type. (default "auto")
   -P, --prettyPrint                     pretty print, shorthand for '... style = ""'
       --properties-array-brackets       use [x] in array paths (e.g. for SpringBoot)
       --properties-separator string     separator to use between keys and values (default " = ")

acceptance_tests/inputs-format-auto.sh

@@ -5,6 +5,7 @@ setUp() {
   rm test*.toml 2>/dev/null || true
   rm test*.tfstate 2>/dev/null || true
   rm test*.json 2>/dev/null || true
+  rm test*.json5 2>/dev/null || true
   rm test*.properties 2>/dev/null || true
   rm test*.csv 2>/dev/null || true
   rm test*.tsv 2>/dev/null || true
@@ -31,6 +32,29 @@ EOM
   assertEquals "$expected" "$X"
 }
 
+testInputJson5() {
+  cat >test.json5 <<'EOL'
+{ /* hello */
+  mike: { things: "cool", },
+}
+EOL
+
+  read -r -d '' expected << EOM
+// hello
+{
+  "mike": {
+    "things": "cool"
+  }
+}
+EOM
+
+  X=$(./yq test.json5)
+  assertEquals "$expected" "$X"
+
+  X=$(./yq ea test.json5)
+  assertEquals "$expected" "$X"
+}
+
 testInputToml() {
   cat >test.toml <<EOL
 [owner]
@@ -84,6 +108,27 @@ EOM
   assertEquals "$expected" "$X"
 }
 
+testInputJson5OutputYaml() {
+  cat >test.json5 <<'EOL'
+{
+  // comment
+  mike: { things: "cool", },
+}
+EOL
+
+  read -r -d '' expected << EOM
+# comment
+mike:
+  things: cool
+EOM
+
+  X=$(./yq test.json5 -oy)
+  assertEquals "$expected" "$X"
+
+  X=$(./yq ea test.json5 -oy)
+  assertEquals "$expected" "$X"
+}
+
 testInputProperties() {
   cat >test.properties <<EOL
 mike.things = hello

acceptance_tests/inputs-format.sh

@@ -7,6 +7,8 @@ setUp() {
   rm test*.tsv 2>/dev/null || true
   rm test*.xml 2>/dev/null || true
   rm test*.tf 2>/dev/null || true
+  rm test*.json5 2>/dev/null || true
+  rm test*.kyaml 2>/dev/null || true
 }
 
 testInputProperties() {
@@ -185,6 +187,40 @@ EOM
   assertEquals "$expected" "$X"
 }
 
+testInputJson5MultilineBlockComments() {
+  cat >test.json5 <<'EOL'
+{
+  /*
+    multiline
+    block comment
+  */
+  first: 1,
+  second/* inline block */: 2,
+  third: /* before value */ 3,
+  fourth: [1, /* between elements */ 2,],
+}
+EOL
+
+  read -r -d '' expected <<'EOM'
+# multiline
+# block comment
+first: 1
+second: 2 # inline block
+third: 3
+# before value
+fourth:
+  - 1
+  # between elements
+  - 2
+EOM
+
+  X=$(./yq e -p=json5 test.json5)
+  assertEquals "$expected" "$X"
+
+  X=$(./yq ea -p=json5 test.json5)
+  assertEquals "$expected" "$X"
+}
+
 
 
 

acceptance_tests/output-format.sh

@@ -48,6 +48,28 @@ EOM
   assertEquals "$expected" "$X"
 }
 
+testOutputJson5() {
+  cat >test.yml <<EOL
+a: {b: ["cat"]}
+EOL
+
+  read -r -d '' expected << EOM
+{
+  "a": {
+    "b": [
+      "cat"
+    ]
+  }
+}
+EOM
+
+  X=$(./yq e --output-format=json5 test.yml)
+  assertEquals "$expected" "$X"
+
+  X=$(./yq ea --output-format=json5 test.yml)
+  assertEquals "$expected" "$X"
+}
+
 testOutputYamlRawDefault() {
   cat >test.yml <<EOL
 a: "cat"

cmd/utils_test.go

@@ -220,6 +220,13 @@ func TestConfigureDecoder(t *testing.T) {
 			expectError:      false,
 			expectType:       "jsonDecoder",
 		},
+		{
+			name:             "json5 format",
+			inputFormat:      "json5",
+			evaluateTogether: true,
+			expectError:      false,
+			expectType:       "json5Decoder",
+		},
 		{
 			name:             "xml format",
 			inputFormat:      "xml",
@@ -390,6 +397,12 @@ func TestConfigureEncoder(t *testing.T) {
 			expectError:  false,
 			expectType:   "jsonEncoder",
 		},
+		{
+			name:         "json5 format",
+			outputFormat: "json5",
+			expectError:  false,
+			expectType:   "json5Encoder",
+		},
 		{
 			name:         "xml format",
 			outputFormat: "xml",
@@ -1265,6 +1278,14 @@ func TestConfigureInputFormat(t *testing.T) {
 			expectInput:   "json",
 			expectOutput:  "json",
 		},
+		{
+			name:          "auto format with json5 file",
+			inputFilename: "file.json5",
+			inputFormat:   "auto",
+			outputFormat:  "auto",
+			expectInput:   "json5",
+			expectOutput:  "json5",
+		},
 		{
 			name:          "auto format with unknown file",
 			inputFilename: "file.unknown",

examples/multiline-comments.json5

@@ -0,0 +1,15 @@
+{
+  /*
+    multiline block comment
+    spanning multiple lines
+  */
+  first: 1,
+  second/* inline block comment */: 2,
+  third: /* before value */ 3,
+  fourth: [
+    1,
+    /* between elements */
+    2,
+  ],
+}
+

examples/sample.json5

@@ -0,0 +1,18 @@
+// JSON5 example file for yq
+{
+  // comments
+  unquotedKey: 'single quoted string',
+  trailingCommaArray: [1, 2,],
+
+  // numbers
+  hexInt: 0x10,
+  posInf: Infinity,
+  negInf: -Infinity,
+  notANumber: NaN,
+
+  nested: {
+    a: 1,
+    b: 2,
+  },
+}
+