diff --git a/docs/src/file-formats.md b/docs/src/file-formats.md
index 3af248ce57..7064b9b49f 100644
--- a/docs/src/file-formats.md
+++ b/docs/src/file-formats.md
@@ -130,6 +130,74 @@ In particular, no encode/decode of `\r`, `\n`, `\t`, or `\\` is done.
* CSV-lite allows changing FS and/or RS to any values, perhaps multi-character.
+* CSV-lite and TSV-lite handle schema changes ("schema" meaning "ordered list of field names in a given record") by adding a newline and re-emitting the header. CSV and TSV, by contrast, do the following:
+ * If there are too few keys, but these match the header, empty fields are emitted.
+ * If there are too many keys, but these match the header up to the number of header fields, the extra fields are emitted.
+ * If keys don't match the header, this is an error.
+
+
+cat data/under-over.json
+
+
+[
+ { "a": 1, "b": 2, "c": 3 },
+ { "a": 4, "b": 5, "c": 6, "d": 7 },
+ { "a": 7, "b": 8 },
+ { "a": 9, "b": 10, "c": 11 }
+]
+
+
+
+mlr --ijson --ocsvlite cat data/under-over.json
+
+
+a,b,c
+1,2,3
+
+a,b,c,d
+4,5,6,7
+
+a,b
+7,8
+
+a,b,c
+9,10,11
+
+
+
+mlr --ijson --ocsvlite cat data/key-change.json
+
+
+a,b,c
+1,2,3
+4,5,6
+
+a,X,c
+7,8,9
+
+
+
+mlr --ijson --ocsv cat data/under-over.json
+
+
+a,b,c
+1,2,3
+4,5,6,7
+7,8,
+9,10,11
+
+
+
+mlr --ijson --ocsv cat data/key-change.json
+
+
+a,b,c
+1,2,3
+4,5,6
+mlr: CSV schema change: first keys "a,b,c"; current keys "a,X,c"
+mlr: exiting due to data error.
+
+
* In short, use-cases for CSV-lite and TSV-lite are often found when dealing with CSV/TSV files which are formatted in some non-standard way -- you have a little more flexibility available to you. (As an example of this flexibility: ASV and USV are nothing more than CSV-lite with different values for FS and RS.)
CSV, TSV, CSV-lite, and TSV-lite have in common the `--implicit-csv-header` flag for input and the `--headerless-csv-output` flag for output.
diff --git a/docs/src/file-formats.md.in b/docs/src/file-formats.md.in
index 601c1bc607..36365a1fb2 100644
--- a/docs/src/file-formats.md.in
+++ b/docs/src/file-formats.md.in
@@ -42,7 +42,7 @@ In particular, no encode/decode of `\r`, `\n`, `\t`, or `\\` is done.
* CSV-lite allows changing FS and/or RS to any values, perhaps multi-character.
-* CSV-lite handles schema changes ("schema" meaning "ordered list of field names in a given record") by adding a newline and re-emitting the header. CSV, by contrast, does the following:
+* CSV-lite and TSV-lite handle schema changes ("schema" meaning "ordered list of field names in a given record") by adding a newline and re-emitting the header. CSV and TSV, by contrast, do the following:
* If there are too few keys, but these match the header, empty fields are emitted.
* If there are too many keys, but these match the header up to the number of header fields, the extra fields are emitted.
* If keys don't match the header, this is an error.
@@ -55,7 +55,7 @@ GENMD-RUN-COMMAND
mlr --ijson --ocsvlite cat data/under-over.json
GENMD-EOF
-GENMD-RUN-COMMAND
+GENMD-RUN-COMMAND-TOLERATING-ERROR
mlr --ijson --ocsvlite cat data/key-change.json
GENMD-EOF
@@ -63,7 +63,7 @@ GENMD-RUN-COMMAND
mlr --ijson --ocsv cat data/under-over.json
GENMD-EOF
-GENMD-RUN-COMMAND
+GENMD-RUN-COMMAND-TOLERATING-ERROR
mlr --ijson --ocsv cat data/key-change.json
GENMD-EOF
diff --git a/docs/src/questions-about-joins.md b/docs/src/questions-about-joins.md
index b8bde2d46d..e3974877ed 100644
--- a/docs/src/questions-about-joins.md
+++ b/docs/src/questions-about-joins.md
@@ -118,9 +118,7 @@ However, if we ask for left-unpaireds, since there's no `color` column, we get a
id,code,color
4,ff0000,red
2,00ff00,green
-
-id,code
-3,0000ff
+3,0000ff,
To fix this, we can use **unsparsify**:
diff --git a/docs/src/record-heterogeneity.md b/docs/src/record-heterogeneity.md
index d02a524482..de96ae69cd 100644
--- a/docs/src/record-heterogeneity.md
+++ b/docs/src/record-heterogeneity.md
@@ -375,13 +375,12 @@ record_count=150,resource=/path/to/second/file
CSV and pretty-print formats expect rectangular structure. But Miller lets you
process non-rectangular using CSV and pretty-print.
-Miller simply prints a newline and a new header when there is a schema change
--- where by _schema_ we mean simply the list of record keys in the order they
-are encountered. When there is no schema change, you get CSV per se as a
-special case. Likewise, Miller reads heterogeneous CSV or pretty-print input
-the same way. The difference between CSV and CSV-lite is that the former is
-[RFC-4180-compliant](file-formats.md#csvtsvasvusvetc), while the latter readily
-handles heterogeneous data (which is non-compliant). For example:
+For CSV-lite and TSV-lite, Miller simply prints a newline and a new header when there is a schema
+change -- where by _schema_ we mean simply the list of record keys in the order they are
+encountered. When there is no schema change, you get CSV per se as a special case. Likewise, Miller
+reads heterogeneous CSV or pretty-print input the same way. The difference between CSV and CSV-lite
+is that the former is [RFC-4180-compliant](file-formats.md#csvtsvasvusvetc), while the latter
+readily handles heterogeneous data (which is non-compliant). For example:
cat data/het.json
@@ -446,19 +445,43 @@ record_count resource
150 /path/to/second/file
-Miller handles explicit header changes as just shown. If your CSV input contains ragged data -- if there are implicit header changes (no intervening blank line and new header line) as seen above -- you can use `--allow-ragged-csv-input` (or keystroke-saver `--ragged`).
+
+mlr --ijson --ocsvlite group-like data/het.json
+
+
+resource,loadsec,ok
+/path/to/file,0.45,true
+/path/to/second/file,0.32,true
+/some/other/path,0.97,false
+
+record_count,resource
+100,/path/to/file
+150,/path/to/second/file
+
-mlr --csv --ragged cat data/het/ragged.csv
+mlr --ijson --ocsv group-like data/het.json
-a,b,c
-1,2,3
+resource,loadsec,ok
+/path/to/file,0.45,true
+/path/to/second/file,0.32,true
+/some/other/path,0.97,false
+mlr: CSV schema change: first keys "resource,loadsec,ok"; current keys "record_count,resource"
+mlr: exiting due to data error.
+
-a,b
-4,5
+Miller handles explicit header changes as just shown. If your CSV input contains ragged data -- if
+there are implicit header changes (no intervening blank line and new header line) as seen above --
+you can use `--allow-ragged-csv-input` (or keystroke-saver `--ragged`).
-a,b,c,4
+
+mlr --csv --allow-ragged-csv-input cat data/het/ragged.csv
+
+
+a,b,c
+1,2,3
+4,5,
7,8,9,10
diff --git a/docs/src/record-heterogeneity.md.in b/docs/src/record-heterogeneity.md.in
index 1aab9dfaae..677098ee87 100644
--- a/docs/src/record-heterogeneity.md.in
+++ b/docs/src/record-heterogeneity.md.in
@@ -180,13 +180,12 @@ GENMD-EOF
CSV and pretty-print formats expect rectangular structure. But Miller lets you
process non-rectangular using CSV and pretty-print.
-Miller simply prints a newline and a new header when there is a schema change
--- where by _schema_ we mean simply the list of record keys in the order they
-are encountered. When there is no schema change, you get CSV per se as a
-special case. Likewise, Miller reads heterogeneous CSV or pretty-print input
-the same way. The difference between CSV and CSV-lite is that the former is
-[RFC-4180-compliant](file-formats.md#csvtsvasvusvetc), while the latter readily
-handles heterogeneous data (which is non-compliant). For example:
+For CSV-lite and TSV-lite, Miller simply prints a newline and a new header when there is a schema
+change -- where by _schema_ we mean simply the list of record keys in the order they are
+encountered. When there is no schema change, you get CSV per se as a special case. Likewise, Miller
+reads heterogeneous CSV or pretty-print input the same way. The difference between CSV and CSV-lite
+is that the former is [RFC-4180-compliant](file-formats.md#csvtsvasvusvetc), while the latter
+readily handles heterogeneous data (which is non-compliant). For example:
GENMD-RUN-COMMAND
cat data/het.json
@@ -200,10 +199,20 @@ GENMD-RUN-COMMAND
mlr --ijson --opprint group-like data/het.json
GENMD-EOF
-Miller handles explicit header changes as just shown. If your CSV input contains ragged data -- if there are implicit header changes (no intervening blank line and new header line) as seen above -- you can use `--allow-ragged-csv-input` (or keystroke-saver `--ragged`).
+GENMD-RUN-COMMAND
+mlr --ijson --ocsvlite group-like data/het.json
+GENMD-EOF
GENMD-RUN-COMMAND-TOLERATING-ERROR
-mlr --csv --ragged cat data/het/ragged.csv
+mlr --ijson --ocsv group-like data/het.json
+GENMD-EOF
+
+Miller handles explicit header changes as just shown. If your CSV input contains ragged data -- if
+there are implicit header changes (no intervening blank line and new header line) as seen above --
+you can use `--allow-ragged-csv-input` (or keystroke-saver `--ragged`).
+
+GENMD-RUN-COMMAND
+mlr --csv --allow-ragged-csv-input cat data/het/ragged.csv
GENMD-EOF
## Processing heterogeneous data
diff --git a/pkg/output/record_writer_tsv.go b/pkg/output/record_writer_tsv.go
index ecb67fd7d4..2a79793b2a 100644
--- a/pkg/output/record_writer_tsv.go
+++ b/pkg/output/record_writer_tsv.go
@@ -12,11 +12,10 @@ import (
)
type RecordWriterTSV struct {
- writerOptions *cli.TWriterOptions
- // For reporting schema changes: we print a newline and the new header
- lastJoinedHeader *string
- // Only write one blank line for schema changes / blank input lines
- justWroteEmptyLine bool
+ writerOptions *cli.TWriterOptions
+ needToPrintHeader bool
+ firstRecordKeys []string
+ firstRecordNF int64
}
func NewRecordWriterTSV(writerOptions *cli.TWriterOptions) (*RecordWriterTSV, error) {
@@ -27,9 +26,10 @@ func NewRecordWriterTSV(writerOptions *cli.TWriterOptions) (*RecordWriterTSV, er
return nil, fmt.Errorf("for CSV, ORS cannot be altered")
}
return &RecordWriterTSV{
- writerOptions: writerOptions,
- lastJoinedHeader: nil,
- justWroteEmptyLine: false,
+ writerOptions: writerOptions,
+ needToPrintHeader: !writerOptions.HeaderlessOutput,
+ firstRecordKeys: nil,
+ firstRecordNF: -1,
}, nil
}
@@ -43,36 +43,22 @@ func (writer *RecordWriterTSV) Write(
return nil
}
- if outrec.IsEmpty() {
- if !writer.justWroteEmptyLine {
- bufferedOutputStream.WriteString(writer.writerOptions.ORS)
- }
- joinedHeader := ""
- writer.lastJoinedHeader = &joinedHeader
- writer.justWroteEmptyLine = true
- return nil
+ if writer.firstRecordKeys == nil {
+ writer.firstRecordKeys = outrec.GetKeys()
+ writer.firstRecordNF = int64(len(writer.firstRecordKeys))
}
- needToPrintHeader := false
- joinedHeader := strings.Join(outrec.GetKeys(), ",")
- if writer.lastJoinedHeader == nil || *writer.lastJoinedHeader != joinedHeader {
- if writer.lastJoinedHeader != nil {
- if !writer.justWroteEmptyLine {
- bufferedOutputStream.WriteString(writer.writerOptions.ORS)
- }
- writer.justWroteEmptyLine = true
+ if writer.needToPrintHeader {
+ fields := make([]string, outrec.FieldCount)
+ i := 0
+ for pe := outrec.Head; pe != nil; pe = pe.Next {
+ fields[i] = pe.Key
+ i++
}
- writer.lastJoinedHeader = &joinedHeader
- needToPrintHeader = true
- }
-
- if needToPrintHeader && !writer.writerOptions.HeaderlessOutput {
for pe := outrec.Head; pe != nil; pe = pe.Next {
bufferedOutputStream.WriteString(
colorizer.MaybeColorizeKey(
- lib.TSVEncodeField(
- pe.Key,
- ),
+ lib.TSVEncodeField(pe.Key),
outputIsStdout,
),
)
@@ -83,24 +69,44 @@ func (writer *RecordWriterTSV) Write(
}
bufferedOutputStream.WriteString(writer.writerOptions.ORS)
+
+ writer.needToPrintHeader = false
+ }
+
+ var outputNF int64 = outrec.FieldCount
+ if outputNF < writer.firstRecordNF {
+ outputNF = writer.firstRecordNF
}
+ fields := make([]string, outputNF)
+ var i int64 = 0
for pe := outrec.Head; pe != nil; pe = pe.Next {
- bufferedOutputStream.WriteString(
- colorizer.MaybeColorizeValue(
- lib.TSVEncodeField(
- pe.Value.String(),
- ),
- outputIsStdout,
- ),
+ if i < writer.firstRecordNF && pe.Key != writer.firstRecordKeys[i] {
+ return fmt.Errorf(
+ "TSV schema change: first keys \"%s\"; current keys \"%s\"",
+ strings.Join(writer.firstRecordKeys, writer.writerOptions.OFS),
+ strings.Join(outrec.GetKeys(), writer.writerOptions.OFS),
+ )
+ }
+ fields[i] = colorizer.MaybeColorizeValue(
+ lib.TSVEncodeField(pe.Value.String()),
+ outputIsStdout,
)
- if pe.Next != nil {
+ i++
+ }
+
+ for ; i < outputNF; i++ {
+ fields[i] = ""
+ }
+
+ for j, field := range fields {
+ if j > 0 {
bufferedOutputStream.WriteString(writer.writerOptions.OFS)
}
+ bufferedOutputStream.WriteString(field)
}
- bufferedOutputStream.WriteString(writer.writerOptions.ORS)
- writer.justWroteEmptyLine = false
+ bufferedOutputStream.WriteString(writer.writerOptions.ORS)
return nil
}
diff --git a/test/cases/io-tsv-auto-unsparsify/at/cmd b/test/cases/io-tsv-auto-unsparsify/at/cmd
new file mode 100644
index 0000000000..818cba82b4
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/at/cmd
@@ -0,0 +1 @@
+mlr -i json -o tsv cat ${CASEDIR}/input.json
diff --git a/test/cases/io-tsv-auto-unsparsify/at/experr b/test/cases/io-tsv-auto-unsparsify/at/experr
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/test/cases/io-tsv-auto-unsparsify/at/expout b/test/cases/io-tsv-auto-unsparsify/at/expout
new file mode 100644
index 0000000000..c0232182d7
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/at/expout
@@ -0,0 +1,4 @@
+a b c
+1 2 3
+4 5 6
+7 8 9
diff --git a/test/cases/io-tsv-auto-unsparsify/at/input.json b/test/cases/io-tsv-auto-unsparsify/at/input.json
new file mode 100644
index 0000000000..832be9c9e2
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/at/input.json
@@ -0,0 +1,17 @@
+[
+{
+ "a": 1,
+ "b": 2,
+ "c": 3
+},
+{
+ "a": 4,
+ "b": 5,
+ "c": 6
+},
+{
+ "a": 7,
+ "b": 8,
+ "c": 9
+}
+]
diff --git a/test/cases/io-tsv-auto-unsparsify/key-change/cmd b/test/cases/io-tsv-auto-unsparsify/key-change/cmd
new file mode 100644
index 0000000000..818cba82b4
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/key-change/cmd
@@ -0,0 +1 @@
+mlr -i json -o tsv cat ${CASEDIR}/input.json
diff --git a/test/cases/io-tsv-auto-unsparsify/key-change/experr b/test/cases/io-tsv-auto-unsparsify/key-change/experr
new file mode 100644
index 0000000000..ce615563a8
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/key-change/experr
@@ -0,0 +1,2 @@
+mlr: TSV schema change: first keys "a b c"; current keys "a X c"
+mlr: exiting due to data error.
diff --git a/test/cases/io-tsv-auto-unsparsify/key-change/expout b/test/cases/io-tsv-auto-unsparsify/key-change/expout
new file mode 100644
index 0000000000..c96a25f193
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/key-change/expout
@@ -0,0 +1,3 @@
+a b c
+1 2 3
+4 5 6
diff --git a/test/cases/io-tsv-auto-unsparsify/key-change/input.json b/test/cases/io-tsv-auto-unsparsify/key-change/input.json
new file mode 100644
index 0000000000..841abab575
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/key-change/input.json
@@ -0,0 +1,17 @@
+[
+{
+ "a": 1,
+ "b": 2,
+ "c": 3
+},
+{
+ "a": 4,
+ "b": 5,
+ "c": 6
+},
+{
+ "a": 7,
+ "X": 8,
+ "c": 9
+}
+]
diff --git a/test/cases/io-tsv-auto-unsparsify/key-change/should-fail b/test/cases/io-tsv-auto-unsparsify/key-change/should-fail
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/test/cases/io-tsv-auto-unsparsify/over/cmd b/test/cases/io-tsv-auto-unsparsify/over/cmd
new file mode 100644
index 0000000000..818cba82b4
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/over/cmd
@@ -0,0 +1 @@
+mlr -i json -o tsv cat ${CASEDIR}/input.json
diff --git a/test/cases/io-tsv-auto-unsparsify/over/experr b/test/cases/io-tsv-auto-unsparsify/over/experr
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/test/cases/io-tsv-auto-unsparsify/over/expout b/test/cases/io-tsv-auto-unsparsify/over/expout
new file mode 100644
index 0000000000..0a61a24061
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/over/expout
@@ -0,0 +1,4 @@
+a b c
+1 2 3
+4 5 6 7
+7 8 9
diff --git a/test/cases/io-tsv-auto-unsparsify/over/input.json b/test/cases/io-tsv-auto-unsparsify/over/input.json
new file mode 100644
index 0000000000..38b47c2f09
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/over/input.json
@@ -0,0 +1,18 @@
+[
+{
+ "a": 1,
+ "b": 2,
+ "c": 3
+},
+{
+ "a": 4,
+ "b": 5,
+ "c": 6,
+ "d": 7
+},
+{
+ "a": 7,
+ "b": 8,
+ "c": 9
+}
+]
diff --git a/test/cases/io-tsv-auto-unsparsify/under/cmd b/test/cases/io-tsv-auto-unsparsify/under/cmd
new file mode 100644
index 0000000000..818cba82b4
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/under/cmd
@@ -0,0 +1 @@
+mlr -i json -o tsv cat ${CASEDIR}/input.json
diff --git a/test/cases/io-tsv-auto-unsparsify/under/experr b/test/cases/io-tsv-auto-unsparsify/under/experr
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/test/cases/io-tsv-auto-unsparsify/under/expout b/test/cases/io-tsv-auto-unsparsify/under/expout
new file mode 100644
index 0000000000..7b24f5bdbf
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/under/expout
@@ -0,0 +1,4 @@
+a b c
+1 2 3
+4 5
+7 8 9
diff --git a/test/cases/io-tsv-auto-unsparsify/under/input.json b/test/cases/io-tsv-auto-unsparsify/under/input.json
new file mode 100644
index 0000000000..e90f7439ad
--- /dev/null
+++ b/test/cases/io-tsv-auto-unsparsify/under/input.json
@@ -0,0 +1,16 @@
+[
+{
+ "a": 1,
+ "b": 2,
+ "c": 3
+},
+{
+ "a": 4,
+ "b": 5
+},
+{
+ "a": 7,
+ "b": 8,
+ "c": 9
+}
+]