Make validate report exit code 2 on schema validation failure (#215)

Signed-off-by: Juan Cruz Viotti <[email protected]>

Author: jviotti

docs/validate.markdown

@@ -18,6 +18,9 @@ information on unsuccessful validation.
 **If you want to validate that a schema adheres to its metaschema, use the
 [`metaschema`](./metaschema.markdown) command instead.**
 
+To help scripts distinguish validation errors, these are reported using exit
+code 2.
+
 Examples
 --------
 

src/command_validate.cc

@@ -178,5 +178,8 @@ auto sourcemeta::jsonschema::cli::validate(
     }
   }
 
-  return result ? EXIT_SUCCESS : EXIT_FAILURE;
+  return result ? EXIT_SUCCESS
+                // Report a different exit code for validation failures, to
+                // distinguish them from other errors
+                : 2;
 }

test/validate/fail_2019_09.sh

@@ -25,7 +25,7 @@ EOF
 
 "$1" validate "$TMP/schema.json" "$TMP/instance.json" 2> "$TMP/stderr.txt" \
   && CODE="$?" || CODE="$?"
-test "$CODE" = "1" || exit 1
+test "$CODE" = "2" || exit 1
 
 cat << EOF > "$TMP/expected.txt"
 fail: $(realpath "$TMP")/instance.json

test/validate/fail_2020_12.sh

@@ -25,7 +25,7 @@ EOF
 
 "$1" validate "$TMP/schema.json" "$TMP/instance.json" 2> "$TMP/stderr.txt" \
   && CODE="$?" || CODE="$?"
-test "$CODE" = "1" || exit 1
+test "$CODE" = "2" || exit 1
 
 cat << EOF > "$TMP/expected.txt"
 fail: $(realpath "$TMP")/instance.json

test/validate/fail_draft4.sh

@@ -25,7 +25,7 @@ EOF
 
 "$1" validate "$TMP/schema.json" "$TMP/instance.json" 2> "$TMP/stderr.txt" \
   && CODE="$?" || CODE="$?"
-test "$CODE" = "1" || exit 1
+test "$CODE" = "2" || exit 1
 
 cat << EOF > "$TMP/expected.txt"
 fail: $(realpath "$TMP")/instance.json

test/validate/fail_draft6.sh

@@ -25,7 +25,7 @@ EOF
 
 "$1" validate "$TMP/schema.json" "$TMP/instance.json" 2> "$TMP/stderr.txt" \
   && CODE="$?" || CODE="$?"
-test "$CODE" = "1" || exit 1
+test "$CODE" = "2" || exit 1
 
 cat << EOF > "$TMP/expected.txt"
 fail: $(realpath "$TMP")/instance.json

test/validate/fail_draft7.sh

@@ -25,7 +25,7 @@ EOF
 
 "$1" validate "$TMP/schema.json" "$TMP/instance.json" 2> "$TMP/stderr.txt" \
   && CODE="$?" || CODE="$?"
-test "$CODE" = "1" || exit 1
+test "$CODE" = "2" || exit 1
 
 cat << EOF > "$TMP/expected.txt"
 fail: $(realpath "$TMP")/instance.json

test/validate/fail_jsonl_all.sh

@@ -22,7 +22,7 @@ EOF
 
 "$1" validate "$TMP/schema.json" "$TMP/instance.jsonl" 2>"$TMP/stderr.txt" \
   && CODE="$?" || CODE="$?"
-test "$CODE" = "1" || exit 1
+test "$CODE" = "2" || exit 1
 
 cat << EOF > "$TMP/expected.txt"
 fail: $(realpath "$TMP")/instance.jsonl (entry #1)

test/validate/fail_jsonl_all_verbose.sh

@@ -22,7 +22,7 @@ EOF
 
 "$1" validate "$TMP/schema.json" "$TMP/instance.jsonl" --verbose 2>"$TMP/stderr.txt" \
   && CODE="$?" || CODE="$?"
-test "$CODE" = "1" || exit 1
+test "$CODE" = "2" || exit 1
 
 cat << EOF > "$TMP/expected.txt"
 Interpreting input as JSONL: $(realpath "$TMP")/instance.jsonl

test/validate/fail_jsonl_one.sh

@@ -22,7 +22,7 @@ EOF
 
 "$1" validate "$TMP/schema.json" "$TMP/instance.jsonl" 2>"$TMP/stderr.txt" \
   && CODE="$?" || CODE="$?"
-test "$CODE" = "1" || exit 1
+test "$CODE" = "2" || exit 1
 
 cat << EOF > "$TMP/expected.txt"
 fail: $(realpath "$TMP")/instance.jsonl (entry #2)